Former Soviet leader Mikhail Gorbachev says tensions between the major powers have put the world "on the brink of a new Cold War".
He accuses the West, particularly the United States, of giving in to "triumphalism" after the collapse of the communist bloc a quarter of a century ago.
Mr Gorbachev spoke today at an event marking the 25th anniversary of the fall of the Berlin Wall, close to the city's Brandenburg Gate.
0 of 3
Mr Gorbachev called for new trust to be built through dialogue with Moscow, and suggested the West should lift sanctions imposed against senior Russian officials over its actions in eastern Ukraine.
He says failure to achieve security in Europe would make the continent irrelevant in world affairs.
Mr Gorbachev's comments echoed those of Roland Dumas, France's foreign minister at the time the Berlin Wall fell.
“Without freedom between nations, without respect of one nation to another, and without strong and brave disarmament policy, everything could start over again tomorrow,” Mr Dumas said. “Even everything we used to know, and what we called the Cold War.”
US president Barack Obama appeared to share some of Mr Gorbachev's concerns for Europe, though he blamed Moscow for the current tensions.
Paying tribute to the East Berliners who pushed past border guards to flood through the Wall on November 9 1989, Mr Obama said in a statement yesterday that “as Russia’s actions against Ukraine remind us, we have more work to do to fully realise our shared vision of a Europe that is whole, free and at peace”.
As Germany prepared for tomorrow's 25th anniversary of the Berlin Wall's collapse, Chancellor Angela Merkel called it a "miracle" that the Cold War barrier was breached without a shot being fired.
In a country with few cheerful anniversaries to celebrate after its belligerent 20th century history, Germans have latched onto memories of the peaceful East German revolution that brought down the Berlin Wall on a joyful November 9th, 1989.
More than 100,000 Berliners and tourists wandered along a 15-km route in the city centre today where the Berlin Wall once stood, and 7,000 illuminated balloons are now perched 3.6-metres high on poles - matching the height of the Wall.
The artistic display of balloons, which dramatically illustrate how the Wall snaked through the heart of the city, is also porous to enable people to easily move back and forth between the former East and West Berlin. The balloons will be released tomorrow to symbolise the Wall‘s disappearance.
Dr Merkel, who was a 35-year-old scientist in Communist East Berlin at the time, told German television ahead of tomorrow’s celebrations that there was tension, fear and excitement in the air in the weeks and days leading up to the opening of the Wall.
“It was a miracle that everything happened peacefully,“ said Dr Merkel, who was on her way home from a visit to the sauna when she saw crowds of people heading west and joined them. “There had been a lot of excitement for weeks. There were tanks that had been on my street since October 7th.“
Dr Merkel, chancellor since 2005, began her career in politics months later as a deputy party spokeswoman. Usually guarded about her life in East Germany, Dr Merkel had until recently been circumspect about revealing details of what she did on the evening the wall opened.
But in recent weeks she has spoken more openly and today said: “After I left the sauna on the evening of November 9th, I went over the Bornholmer Street crossing to the other side and celebrated there with total strangers.
“There was just this incredible feeling of happiness,“ added Dr Merkel, who had recently revealed that she went to a flat with strangers in West Berlin and wanted to call an aunt in the West, and then returned to East Berlin a few hours later because she had to get to work early the next morning.
“It was a night I‘ll never forget,” Dr Merkel said.
The Berlin Wall was built in 1961 to stop East Germans fleeing to the West. It began as a brick wall and was then fortified as heavily guarded 160 km (100 mile) double white concrete screen that encircled West Berlin, cutting across streets, between families, and through graveyards.
At least 136 people were killed trying to flee to West Berlin and many ended up in jail for their attempts to escape.
Communist regimes across Eastern Europe collapsed in 1989, heralding the end of the Cold War, of which the Berlin Wall had become a potent symbol.
Reuters