KIEV, Oct. 13 - President Petro Poroshenko proposed a new defense minister on Monday after the previous incumbent resigned amid sharp criticism over a rout of Kiev's troops by Russian-backed separatists in late August, Reuters reported.

The presidential website named Stepan Poltorak, 49, head of Ukraine's National Guard, as Poroshenko's choice to replace Valery Heletey. Parliament is expected to vote on the nomination on Tuesday.

By replacing his defense minister now, two weeks before a parliamentary election in Ukraine, political analysts said Poroshenko was trying to disarm critics of his record in tackling the pro-Russian rebels in the east of the country.

Heletey had faced heavy criticism after Ukrainian forces suffered a crushing defeat at rebel hands on Aug. 24 at Ilovaisk, east of the main rebel-held eastern city of Donetsk.

That setback, in which Kiev says more than 100 Ukrainian military personnel were killed, prompted Poroshenko to accept the need for a ceasefire and a diplomatic resolution of the conflict in eastern Ukraine, military sources say.

The sources say a large number of Russian troops were also killed at Ilovaisk - a charge not acknowledged by Moscow, which denies any part in the Ukraine conflict despite what Kiev and Western governments say is incontrovertible proof.

Heletey defended himself on Monday, denying any mistakes had been made at Ilovaisk and repeating his contention that Russian forces had suffered heavy losses too.

"The flow of dead Russian servicemen stopped the aggression of (Russian President Vladimir) Putin, of Russian forces. This was a large-scale offensive (by Russia) on the territory of Ukraine," he said.

Political analysts linked Heletey's resignation to the Oct. 26 parliamentary election, in which Poroshenko's own political bloc is expected to perform strongly.

"Heletey attracted too much that was negative. As long as Heletey was seen as Poroshenko's man this would tell on Poroshenko's ratings," political analyst Ostap Kryvdyk said.

Kiev's pro-Western leadership hope the election will provide a solid platform in parliament to push forward with Poroshenko's peace plan in eastern Ukraine while keeping the country on its course towards closer European integration.

But Poroshenko also faces internal opposition from parties who fear he may make too many concessions to the separatist leaders in the heavily industrialized, mainly Russian-speaking east, who are pressing for unity with Russia.

The ceasefire declared on Sept. 5, which is central to Poroshenko's peace plan, is also under renewed strain as government forces clash with the rebels around Donetsk airport and in several other eastern districts.

The United Nations says more than 3,600 people - Ukrainian troops, separatists and civilians - have been killed in eastern Ukraine since the fighting erupted there in April. (rt/ez)