"The prime minister has made clear that he's ready to consider putting UK boots on the ground in the circumstances of a negotiated peace," Healey told ITV television channel.

His comments came as NATO military chiefs from the alliance's 32 member countries were to hold a virtual meeting on Wednesday.

The military head of NATO's forces in Europe, US General Alexus Grynkewich, was to give an update "on the current security environment" as "diplomatic efforts to secure peace in Ukraine progress", the head of the alliance's military committee said.

Top US and European military officers met in Washington Tuesday to discuss the mechanics of a possible Ukraine peace deal.

Shortly before that, President Donald Trump had ruled out sending US troops to back an agreement but suggested air support instead.

Healey said UK and "many other nations" wanted to support Ukraine to deter any future Russian hostilities and provide assurances that "we will stay with them to try and secure a long-term peace".

Security minister Dan Jarvis told Sky News on Wednesday that "more than 200 military planners from 30 nations" had been working together to set up the body, dubbed the coalition of the willing.

The UK must be "ready to step in in the event of a permanent ceasefire, with a multinational force led by Britain and France that is prepared to try and secure that peace for the long term", he said.

As Ukraine rebuilds, "we can play a part in those early days in securing the skies and seas as well", Jarvis added.

jkb/har/jj

ITV