UK defence minister Michael Fallon reassured Ukrainian prime minister Arseniy Yatsenyuk of Britain's increased support to train the country's army when the pair met in capital Kiev on 11 August.
Fallon said: "This must not be allowed to become a frozen conflict. It seems to me pretty red hot given how many of your own troops have been killed since the signing of the peace agreement, and the numbers wounded. I am here to reaffirm our support for Ukraine and its fight for freedom, its right to territorial integrity and its right to have its borders respected."
Fallon also met his Ukrainian counterpart Stepan Poltorak and said Britain will increase its contribution to military training.
"I am setting the British army a new target to train more than 2,000 members of the Ukrainian military by the end of this financial year. So that that training can be cascaded through the entire Ukrainian military and that the trainers we have trained can, in turn, train others," Fallon said.
Several countries have recently made similar offers. Canada and Poland have pledged to send 200 and 50 instructors respectively this year.
About 310 members of the US Army's 173rd Airborne Brigade, based in Vicenza, Italy, are currently training the second of three battalions of Ukrainian national guardsmen in western Ukraine near the Polish border.
Training of the third battalion is expected to conclude by 15 November, after which the US and other Western allies could begin training regular Ukrainian military forces, if they can agree on the details and a training programme with Kiev.