With tensions high over the Ukraine conflict and Russia`s backing of the Syrian regime, Medvedev said: "All that`s left is an unfriendly policy of NATO against Russia".
"We can say it even more clearly: We have slid into a new period of Cold War," he said, speaking at the Munich Security Conference.
"Almost every day we are accused of making new horrible threats either against NATO as a whole, against Europe or against the US or other countries."
Medvedev criticised the expansion of NATO and EU influence deep into formerly Soviet-ruled eastern Europe since the end of the Cold War.
"European politicians thought that creating a so-called belt of friends at Europe`s side, on the outskirts of the EU, could be a guarantee of security, and what`s the result?" he said.
"Not a belt of friends but a belt of exclusion."
He added that "creating trust is hard ... but we have to start. Our positions differ, but they do not differ as much as 40 years ago when a wall was standing in Europe."
Paris:French government spokesman Stephane Le Foll says a seven-hour police operation north of Paris targeting the mastermind of the Paris attacks and his accomplices, has ended. Le Foll spoke to reporters in the presidential palace after a Cabinet meeting, saying, "The operation is over."
Police say two people were killed in the operation Wednesday including a female suicide bomber. Several police were injured and seven people were arrested. The fate of the mastermind Abdelhamid Abaaoud is unclear.
A woman wearing an explosive suicide vest blew herself up Wednesday as heavily armed police tried to storm a suburban Paris apartment where the suspected mastermind of last week's attacks was believed to be holed up, police said.
They said one man was also killed and seven people arrested in the standoff, which began before dawn and continued more than five hours later. One person remained holed up in the apartment, but it wasn't clear who. A senior police official and the Paris prosecutor's office say that the seven were arrested Wednesday in the building in the Paris suburb of Saint-Denis.
Meanwhile, all 129 fatalities in the attacks have now been identified but dozens of other casualties remain in critical condition, a statement from the French cabinet said.
"To date, of the dead victims have all been identified, that is 129," said the statement issued after the weekly cabinet meeting. A total of 221 people remain in hospital, dozens of them seriously hurt.
A senior police official said he believed Abdelhamid Abaaoud, a Belgian Islamic State militant, was inside the apartment in the Paris suburb of Saint-Denis with five other heavily armed people.
The official, who was not authorised to be publicly named according to police rules but is informed routinely about the operation, said scores of police stormed the building and were met with unexpectedly violent resistance.
Another police official not authorized to be publicly named because of police rules said four police officers were injured. No hostages were being held.
The Paris prosecutor's office said SWAT teams arrested seven people in the apartment. It said they haven't been identified yet.
Residents said an explosion shook the neighbourhood at about 4 a.m. (0300GMT).
"Then there was second big explosion. Then two more explosions. There was an hour of gunfire," said Baptiste Marie, a 26-year-old independent journalist who lives in the neighbourhood.
Another witness, Amine Guizani, said he heard the sound of grenades and automatic gunfire.
"They were shooting for an hour. Nonstop. There were grenades. It was going, stopping. Kalashnikovs. Starting again," Guizani said.
Sporadic bangs and explosions continued, and at 7:30 a.m. (0630GMT) at least seven explosions shook the center of Saint-Denis. Associated Press reporters at the scene could hear what sounded like grenade blasts from the direction of the standoff.
Investigators have identified 27-year-old Abaaoud, a Belgian of Moroccan descent, as the chief architect of Friday's attacks in Paris, which killed 129 people and injured 350 others.
A US official briefed on intelligence matters said Abaaoud was a key figure in an Islamic State external operations cell that US intelligence agencies have been tracking for many months.
Police vans and fire trucks rushed to the scene north of Paris, less than two kilometers (just over a mile) from the Stade de France stadium. Three suicide bombers blew themselves up Friday near the stadium during an international soccer match with French President Francois Hollande in attendance.
In Saint-Denis on Wednesday, police cordoned off the area nearby, including a pedestrian zone lined with shops and 19th-century apartment buildings. Riot police cleared people from the streets, pointing guns at curious residents to move them off the roads.
Saint-Denis is one of France's most historic places. French kings were crowned and buried through the centuries in its famed basilica. Today it is home to a vibrant and very ethnically diverse population and sees sporadic tension between police and violent youths.
Saint-Denis Mayor Didier Paillard said public transport was suspended and that schools in the center of town would not open Wednesday.
Seven attackers died in Friday's gun-and-bomb rampage through Paris. The Islamic State group has claimed responsibility for the carnage.
Police had said before the raids that they were hunting for two fugitives suspected of taking part as well as any accomplices. That would bring the number of attackers to at least nine.
French authorities had previously said that at least eight people were directly involved in the bloodshed: seven who died in the attacks and one who got away and slipped across the border to Belgium.
However, there have been gaps in officials' public statements, which have never fully disclosed how many attackers took part in the deadly rampage.
On Tuesday, officials told The Associated Press they now believe at least one other attacker was involved and they were working to identify and track down that suspect. Three officials spoke on condition of anonymity because they were not authorized to provide details about the ongoing investigation.
Surveillance video obtained by the AP also indicated that a team of three attackers carried out the shootings at one of the cafes. The video was among evidence authorities used in concluding that at least one other attacker was at large, the French officials indicated.
The brief clip shows two black-clad gunmen with automatic weapons calmly firing on the bar then returning toward a waiting car, whose driver was maneuvering behind them. Authorities believe the car is the same black SEAT-make vehicle that was found Saturday with three Kalashnikovs inside.
Police have identified one subject of their manhunt as Salah Abdeslam, whom French police accidentally permitted to cross into Belgium on Saturday. One of his brothers, Brahim, blew himself up in Paris.
A resident of the Paris suburb of Saint-Denis described intense gunfire and explosions during a police operation near the site of one of last week's deadly attacks.
Baptiste Marie, a 26-year-old independent journalist who lives near the scene of the standoff, said, "It started with an explosion. Then there was second big explosion. Then two more explosions. There was an hour of gunfire."
Resident Amin Guizani, 21, says: "There were grenades. It was going, stopping. Kalashnikovs. Starting again."
Riot police were clearing the streets early Wednesday, pointing guns at curious residents to move them off the roads.
Marie said the officers seemed nervous.
"You could see it in their eyes, " Marie said.
The shootout came as France remains on high alert after a video revealed a ninth man may have taken part in the Paris attacks. Terror group Islamic State has claimed the bloodshed.
Police across Europe are hunting the newest suspect, after footage showed a third man in a car used by gunmen who opened fire at bars and restaurants in central Paris.
It is not clear if this ninth man is one of two suspected accomplices detained in Belgium or is on the run, potentially with 26-year-old fugitive Frenchman Salah Abdeslam who carried out one of the attacks at Bonne Biere cafe along with his suicide-bomber brother Brahim.
French President Francois Hollande on Wednesday will hold a meeting to discuss proposals to extend the state of emergency declared after the worst attacks in French history for three months. It will then be put to vote by lawmakers Thursday and Friday.
In a sign of the nervousness gripping Europe after Friday's carnage, a football match between Germany and the Netherlands was cancelled on Tuesday and the crowd evacuated after police acted on a "serious" bomb threat.
French President Francois Hollande says France is 'at war' against terrorism by the Islamic State group.
Hollande says he wants "large coalition" working together against IS militants to destroy a group that threatens the whole world and "commits massacres" in the Mideast.
Hollande says "we are at war." He was speaking in a televised address Wednesday after a seven-hour police siege on an apartment north of Paris where police suspected the mastermind of the deadly Paris attacks might have been.
He says the French aircraft carrier Charles de Gaulle just left to help French military operations in Syria against IS.
Victims of a shooting attack lay on the pavement outside La Belle Equipe restaurant in Paris
France's security services are once again facing a harsh spotlight after failing to prevent the brutal attacks in Paris carried out by the Islamic State group.
There is particular concern over the failure to intercept Samy Amimour, the 28-year-old Frenchman who is now on the run after the attacks.
A case was opened against him in France in 2012 after an abortive attempt to go to Yemen, but he was still able to travel to Syria a year later, triggering an international warrant for his arrest.
That did not stop him sneaking back into France and taking part in Friday's bloody attacks in the capital.
"We have a problem with controlling (Europe's) Schengen borders -- a big one," said Alain Chouet, a former security chief at France's DGSE external intelligence service.
"(Amimour's) arrival should have triggered a red flag. But these guys understand very well the techniques for entering and exiting the Schengen zone. They've practised it a lot."
The intelligence services are also taking flak over one of the gunman who blew himself up at the Bataclan concert hall, Omar Ismail Mostefai. He had been on the radar since 2010 and was subject to an "S-file" as a known extremist.
Turkey says it alerted France that he was a potential threat on two occasions -- in December and January -- after he travelled to the country in 2013, likely on his way to Syria.
But Turkey "never got a response from France", a senior official in Ankara said.
Belgium represents another major problem for European security, with several of the attackers known to local police but little done to track their movements.
"You understand that if the Belgians don't warn us, we can't do anything," a senior French police source said Monday.
Overwhelming numbers
Despite the criticism, experts say the scale of the challenge makes it impossible to keep track of everything.
"Fingers will be pointed at the French intelligence services but given the sheer number of individuals they have to monitor, they are finding it overwhelming, and it was always likely that some would slip through the net," said Kit Nicholl, France security analyst for IHS Country Risk in London.
France has contributed the highest number of citizens to the jihad in Syria and Iraq.
More than 500 French fighters are thought to be with Islamic State in Syria and Iraq, according to official figures, while 250 have returned and some 750 expressed a desire to go there. More than 10,000 people have "S-file" status as potential extremists.
France passed a new legal framework over the summer, giving the authorities sweeping powers to bug phones and online conversations with little judicial oversight.
But as with the case of the Kouachi brothers who carried out the attacks on Charlie Hebdo magazine in January, "it's clear the problem isn't identifying potential terrorists, it's having the resources for analysis and assessment," said Nicholl.
"Those with training abroad will probably have the awareness of how to circumvent surveillance, either by avoiding communications altogether or using advanced encryption technologies that are advancing at such a pace that it's hard for intelligence agencies to stay ahead," he added.
A former counter-terrorism specialist for the DGSE, speaking on condition of anonymity, said there were three theories.
"Either no one saw anything, and that's a big worry, or we saw things and we didn't understand them, which is also a problem, or we saw things and despite everything they were able to carry out the attack," he said.
"It means we either have a problem of intelligence, or analysis of the intelligence, or of the chain of command among the security services. The challenge was made harder by the fact it was prepared in Belgium."
"It has to be said: even though the Belgians have the highest proportion of people leaving for Syria, they are not up to the task. In this group, many of the guys were known in Brussels.
"Someone has screwed up," he said.
But counter-terrorism officials are forced to make difficult choices about which people to prioritise with limited resources.
"It stops me sleeping at night," said a French counter-terrorism official in a recent interview prior to the attacks. "How do you put the right names in the right place on the list -- we are very far from an exact science."
Others said the blame should not ultimately land on the security services.
"Clearly if there was an attack, there's a problem," said Chouet.
"But you don't blame the forest fire on the firefighters."
