French President Emmanuel Macron has told reporters that President Vladimir Putin assured him that Russian forces would not ramp up the crisis near Ukraine’s borders.
“I secured an assurance there would be no deterioration or escalation,” he said before meeting Ukraine’s leader.
However, Russia said any suggestion of a guarantee was “not right”.
Russia has denied any plans to invade Ukraine, but it has assembled more than 100,000 troops near its borders.
US officials believe Russia has assembled 70% of military forces needed for a full-scale invasion.
The tensions between Russia, Ukraine and the West come nearly eight years after Russia annexed Ukraine’s southern Crimea peninsula.
Moscow accuses the Ukrainian government of failing to implement the Minsk agreement – an international deal sponsored by Germany and France to restore peace to the east, where Russian-backed rebels control swathes of territory and at least 14,000 people have been killed since 2014.
President Macron this week is on a diplomatic tour of national capitals. He arrived in the Ukrainian capital, Kyiv, on Tuesday after almost six hours of talks with Mr Putin in Moscow on Monday.
At a news conference with Ukraine’s President Volodymyr Zelensky, Mr Macron said there was now the chance to “make these negotiations move forward” between Russia and Ukraine, and that he could see “concrete solutions” to reducing tensions.
Mr Zelensky meanwhile called on Mr Putin to take serious measures to reduce tensions. “I do not really trust words, I believe that every politician can be transparent by taking concrete steps,” he said.