Ukrainian President Volodymyr Zelenskiy on Wednesday hailed this week's meeting in Saudi Arabia between U.S. and Ukrainian officials as constructive, and said a potential 30-day ceasefire with Russia could be used to draft a broader peace deal.

The Kremlin said it needed to be briefed by the U.S. before it would comment on whether a proposed Ukraine ceasefire was acceptable to Russia.

Ukraine has launched its biggest drone attack yet on Moscow as its diplomats are meeting the US to discuss how to end the war. Also on the programme: gunmen in Pakistan seize a passenger train with hundreds on board;