Defense Secretary Michael Fallon pledged additional support for Ukraine when he spoke at the NATO Defense Ministerial in Brussels.
Fallon says British troops will be deployed to the Baltic states and Poland on a regular basis for training purposes, and build on existing deployments where it can.
"We are committed to supporting the sovereignty of the democratic nations of Eastern Europe. We are already deploying RAF jets to the Baltics and providing crucial training to the Ukrainian armed forces," Fallon said.
"Now we will have a more regular drumbeat of troops deploying in the Baltics and Poland, and will step up our training effort in Ukraine."
Nineteen teams from the United Kingdom have deployed to Ukraine to train almost 1,600 members of the Ukraine Armed Forces since the conflict in the country began.
The training includes skills for infantry, medical, logistics and tactical intelligence.
The move has Britain joining the United States and other Western allied powers in Europe in supporting Ukranian president Petro Poroshenko and his armed forces against Russian-backed militants in eastern Ukraine.
The contribution is part of the U.S.-German Transatlantic Capability Enhancement and Training initiative, which the U.K. Ministry of Defense says builds on the country's policing of the Baltic region.
Moscow support for Ukrainian separatists has been one of the factors putting Russia in the worst standing with NATO powers since the end of the Cold War.
More recently, Russian military action in Syria has drawn condemnation from NATO and U.S. officials.