The failure of the United States and its Western allies to offer vital aid amid the break-up of the Soviet Union 25 years ago was short-sighted gloating at the Cold War rival's demise and wasted the chance to build a safer world, the bloc's former supremo Mikhail Gorbachev has said.
But Mr Gorbachev, 85, the Soviet Union's last leader, voiced hope that Russia and the United States would do better and ease current tensions during Donald Trump's presidency.
"The relations between us are so important and concern everyone else, so we must take the interests of others into account," said the man credited with helping to end the Cold War.
Mr Gorbachev said he had expected Hillary Clinton to win the US presidential race and was surprised by Mr Trump's victory. He declined to offer an assessment of Mr Trump, saying it remained to be seen what policies the new US administration would pursue.
"He has little political experience, but, maybe, it's good," he said, during the rare, hour-long interview with The Associated Press at his foundation's office in Moscow.
Mr Gorbachev, who helped end the Cold War by launching sweeping liberal reforms, cutting nuclear stockpiles and allowing Soviet bloc nations in central and eastern Europe to break free from Moscow's diktat, spoke bitterly about the West's failure to embrace a new era of friendly co-operation he said his policy of "perestroika" offered.
"They were rubbing their hands, saying, 'How nice! We had been trying to do something about the Soviet Union for decades, and it ate itself up!'," he said.
He attacked what he described as Western "triumphalism" saying it remains a key factor in tensions between Russia and the West.
Ties between them are worse than they have been at any time since the Cold War following Moscow's annexation of Ukraine's Crimea peninsula in March 2014 and its support for a pro-Russian separatist uprising in eastern Ukraine.
The US and the European Union responded with several rounds of economic sanctions, which, along with low oil prices, have driven Russia's economy into recession.
Russian president Vladimir Putin has accused the US of trying to isolate and weaken the nation, pointing to the deployment of Nato forces near Russia's borders as a sign of hostile intentions and the war in Syria, where Russia has waged an air campaign in support of President Bashar Assad, has added to the tensions.
Mr Gorbachev said Russian and US leaders must sit down for talks and "stay at the table until they reach agreement".
"The world needs Russia and the United States to co-operate," he said. "Together, they could lead the world ... to a new path."
He defended Russia's action to annex Crimea, pointing out that Soviet leader Nikita Khrushchev arbitrarily transferred Crimea from Russian to Ukrainian administrative control in 1954, a decision that mattered little until the Soviet collapse.
He also noted that the annexation followed a popular vote in which the residents of the Black Sea peninsula overwhelmingly backed joining Russia.
"When people say yes, a decision must be made," he said.
Mr Gorbachev also praised outgoing US president Barack Obama, but deplored what he described as a misguided policy towards Russia pursued by the US and its allies, both during his presidency and now.
"They have been badgering Russia with accusations and blaming it for everything," he said. "And now, there is a backlash to that in Russia. Russia wants to have friendly ties with America, but it's difficult to do that when Russia sees that it's being cheated."
Mr Gorbachev pointed to the productive relationship he built with Ronald Reagan during the 1980s and the arms control agreements they reached despite sharp ideological differences.
"We accomplished a lot," he said. "We could talk openly, in a real partner-like way. It's necessary to take that approach again."
Asked his opinion of Mr Putin's leadership, Mr Gorbachev said he saw him as a "worthy president", even though he has criticised some of his policies.
In the past, Mr Gorbachev assailed the Kremlin for a crackdown on freedom of speech and rigid political controls. He also was critical of Mr Putin's return to the presidency in 2012 after term limits forced him to switch to the premier's seat for four years.
"I almost fully supported him first, and then I began to voice criticism," Mr Gorbachev said of Mr Putin. "I can't renounce my views."
He added, however, that he approved of Mr Putin's recent state-of-the-nation address. The speech sent a conciliatory message to the West, and some observers also saw signs that the Kremlin may ease some of its rigid domestic policies.
"It was different from his previous speeches," Mr Gorbachev said. "The speech showed that he's strongly worried."
He recalled the waning days of the Soviet Union, when his arch-foe, Russian Federation president Boris Yeltsin, and leaders of other Soviet republics plotted his removal while pretending to support his efforts to negotiate a treaty that would give the republics broader powers.
"Yeltsin took part in that and supported it, but he was conspiring behind my back how to get rid of Gorbachev," he said, claiming that a hunger for power motivated the Russian leader. "Russia was spearheading the Soviet break-up."
Asked if he considered using force to prevent the Soviet break-up, Mr Gorbachev said launching a violent domestic conflict in a nuclear superpower was never an option for him.
"The country was loaded to the brim with weapons," he said. "And it would immediately have pushed the country into a civil war."