LUHANSK: Pro-Russian insurgents in eastern Ukraine have taken two government bases in battles around Luhansk.

They seized quantities of ammunition and explosives from a border guards post and taking another installation after National Guard forces ran out of ammunition.

The border guards answer directly to Ukraine's president while the National Guard is part of the country's police troops.

Officials said in a statement on Wednesday that six militants were killed and three Ukrainian servicemen were injured in 10 hours of fighting overnight at the National Guard base.

Rebels seized a border guards’ base on the outskirts of Luhansk following a nearly two-day-long siege.

An Associated Press reporter saw pro-Russian militia carrying crates of ammunition and explosives out of the base Wednesday and driving away in border guards' cars.

There was no immediate report of casualties in the fighting at the border guards’ base.

Ukraine's fledging government has blamed the recent military failures on the administration of the former President Viktor Yanukovych which, they claim, has left the army penniless and poorly trained.

The defence ministry set up a charity account to support the armed forces while volunteers across the country have been buying provisions for the soldiers.

The fighting in Ukraine's east has escalated following the May 25 presidential election won by billionaire candy magnate Petro Poroshenko, with rebels launching an attack on a major airport and shooting down a government helicopter elsewhere.

Ukrainian troops on Tuesday launched an offensive against pro-Russian insurgents in the eastern city of Slovyansk.

“Two government soldiers were killed and 42 injured in daylong fighting,” Vladislav Seleznyov, press secretary for Ukraine's operation against the rebels in the east, told Ukrainian news agencies.

Seleznyov put the death toll of the rebels at 300 but the insurgents did not confirm these reports.

US President Barack Obama met with Poroshenko in Warsaw on Wednesday and praised Poroshenko for reaching out to the country's restive east.

The White House also said the US would send $5 million in equipment to Kiev including, for the first time, body armour and night-vision goggles for the use of troops.

The United States already has provided ready-to-eat meals and money for medical supplies and other non-lethal assistance, including clothing, sleeping bags and generators.

In Kiev, interim President Oleksandr Turchynov, who will hand over to Poroshenko on Saturday, has asked the country's Security and Defence Council to consider imposing martial law in parts of eastern Ukraine in a bid to stabilise the situation.

Ukraine's prime minister, defence, interior ministers as well as heads of other security and intelligence agencies are all members of the council.

Turchynov was reported to have left for a visit to eastern Ukraine on Wednesday.

Ukraine's deputy prime minister Vitaly Yarema was quoted by the Interfax Ukraine news agency as saying that the council will convene to discuss martial law only after Poroshenko's inauguration on Saturday.