Gorbachev, whose policy of "perestroika" (restructuring) played a role in ending the Cold War, warned of potentially dire consequences if tensions were not reduced.
"This is extremely dangerous, with tensions as high as they are now. We may not live through these days: someone could lose their nerve," he wrote in a commentary entitled "To unfreeze relations" for government dailyRossiyskaya Gazeta.
"I suggest the leaders ofRussiaand theUnited Statesthink about holding a summit with a broad agenda, without preliminary conditions," he wrote. "One needn't be afraid of 'losing face', that someone will gain a propaganda victory: this should all belong to the past. One needs to think about the future."
The diplomatic standoff overUkraineis the worst betweenMoscowand the West since the Cold war ended more than two decades ago. Gorbachev warned of a new Cold War last month at an event marking the fall of theBerlinWall.
Russiadenies providing the rebels with military support and fends off Western criticism of its annexation of Crimea in March, saying the Crimean people voted for it in a referendum.
Relations between the U.S. and Russian presidents,Barack ObamaandVladimir Putin, are strained and Obama pulled out of a summit planned with Putin in St Petersburg in September 2013. They last met, briefly, at a G20 summit inBrisbanelast month.
"Judging by recent statements, diplomats on both sides are bracing for long-term confrontation," wrote Gorbachev, who is widely respected abroad but has few backers inRussia.