KIEV, Aug. 7 - A native of eastern Ukraine on Thursday replaced a Russian as leader of separatists in their stronghold of Donetsk, in a move aimed at blunting Western accusations the rebellion is being run by Moscow, Reuters reported.

Aleksander Borodai, one of several Russian nationals in top roles among the pro-Moscow rebels as the head of the self-proclaimed "Donetsk People's Republic" (DNR), told a news conference he would now serve as deputy to the new leader.

The new head of the separatist rebels, Alexander Zakharchenko, was sitting to his left in a conference room in what used to be the Donetsk regional administration building until it was turned the rebels' headquarters.

"He is a real commander, a clever person, a great manager," Borodai said of Zakharchenko, who was sporting a green camouflage jacket.

A native of Donetsk in his late 30s, Zakharchenko commands a heavily armed rebel unit called Oplot, which has taken part in some of the fiercest battles and had its origins in a martial arts club.

He was among the first separatists to occupy the regional administration building in Donetsk when pro-Russian crowds captured it in March following the ousting of a Moscow-allied president in Kiev.

The nomination of a seasoned fighter to head the DNR also comes as fighting intensifies in eastern Ukraine where Kiev troops have pressed ahead with a campaign against the pro-Russian rebellion and recaptured some ground in recent weeks.

Fighting intensified after Ukraine's new, pro-Western President Petro Poroshenko was inaugurated in early June and stepped up again after a Malaysian airliner was shot down over rebel-held territory on July 17, killing all 298 on board.