Ukraine welcomes the possibility of a summit between U.S. President Joe Biden and Russian President Vladimir Putin but nothing can be solved without Kyiv's involvement, Ukraine's top security official said on Monday.

"No one can resolve our issue without us," Oleksiy Danilov told a briefing. "Everything should happen with our participation."

Biden and Putin have agreed in principle to a summit over Ukraine, France's President Emmanuel Macron said on Monday, offering a possible path out of one of the most dangerous European crises in decades.