(Refiles to clarify UK and NATO involvement, add UK statement)
KYIV (Reuters) - Ukraine and Britain will conduct joint military drills this summer involving NATO member troops, Ukrainian defence officials said on Saturday, a step that could irritate Moscow.
The General Staff of the Armed Forces of Ukraine said in a statement that the drills would involve more than 1,000 military personnel from at least five states in the transatlantic NATO military alliance.
NATO voiced concern on Thursday over what it said was a big Russian military build-up near eastern Ukraine after Russia warned that a serious escalation in the conflict in Ukraine's Donbass region could "destroy" Ukraine.
The Kremlin on Friday said that any deployment of NATO troops to Ukraine threatened stability near Russia's borders and may force Moscow to take extra measures to ensure its own security.
Ukrainian troops have battled Russian-backed separatist forces in the eastern Donbass region in a conflict Kyiv estimates has killed 14,000 people since 2014.
Ukraine said the drills, called Cossack Mace, were large-scale international exercises that would strengthen cooperation between Ukrainian forces and NATO armies.
"In particular, defensive actions will be worked out, followed by an offensive in order to restore the state border and territorial integrity of a state that has been subjected to aggression by one of the hostile neighbouring countries," the statement said.
A representative for Britain's Ministry of Defence said Cossack Mace was a routine exercise still in planning for the summer.
(Reporting by Ilya Zhegulev; Writing by Alexander Marrow; Editing by Christina Fincher)