Both sides gave their most upbeat assessments after weekend negotiations. "Russia is already beginning to talk constructively," Ukrainian negotiator Mykhailo Podolyak said in an earlier video online, adding that he thinks the two sides will achieve some results literally in a matter of days.

A Russian delegate to the talks, Leonid Slutsky, was quoted by the RIA news agency as saying they had made significant progress and it was possible the delegations could soon reach draft agreements.

Ukrainian President Volodymyr Zelenskiy said the countries' delegations have been speaking daily by video link and a clear aim of his negotiators was to try to arrange for him to meet President Putin.