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LONDON, Feb 25 (Reuters) - Britain ruled out deploying combat troops to Ukraine on Wednesday, a day after it said it was sending 75 military advisers and trainers to help the Ukrainian army reduce its fatality rate against pro-Russian separatists.

Speaking in parliament, Defence Minister Michael Fallon stressed the training mission, which will begin in mid-March, was "closely defined" and was being undertaken at the request of the Ukrainian government.

He said it wasn't the start of a wider intervention and that Britain would not be deploying combat troops to Ukraine, which is fighting pro-Russian separatists along its eastern flank.

"We are not deploying combat troops to Ukraine and will not do so," Fallon said, when asked whether the deployment of military personnel would provoke so-called "mission creep".

Prime Minister David Cameron announced the training mission on Tuesday, warning that Moscow would move to destabilise other countries if left unchallenged.

Fallon said British personnel would conduct the training in Kiev and western Ukraine. Britain was considering a Ukrainian request for equipment and supplies, he added, but had no plans to provide lethal assistance to Kiev. (Reporting by Andrew Osborn and Guy Faulconbridge; Editing by Stephen Addison)

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