MOSCOW (AFP) - President Vladimir Putin stuck to his guns as he refused to say where Moscow-backed Ukrainian separatists receive heavy arms from and said that people fighting a just cause "will always get weapons".

"Where did they get the armoured vehicles and the artillery systems?" Mr Putin said in reply to a question from German TV network ARD in an interview broadcast Sunday.

"Nowadays people who wage a fight and consider it righteous will always get weapons." "But I would like to stress that this is not the issue," he added. "The issue is that we can't have a one-sided view of the problem."

Kiev and the West accuse Russia of sending regular troops into Ukraine to help buttress a pro-Moscow separatist insurgency in which over 4,100 people have been killed over the past seven months. Mr Putin has repeatedly denied the claim.

At the weekend the Kremlin strongman faced scorn from Western leaders at the G20 summit in Brisbane, where he was isolated and which he left early.

In an interview recorded just before the G20 summit and released in Russia early Monday, Mr Putin also said he was worried about possible "ethnic cleansing" in Ukraine.

"Frankly speaking, we are very concerned about possible ethnic cleansing and Ukraine ending up as a neo-Nazi state," Mr Putin said in the interview recorded on Thursday in Vladivostok. He reiterated his criticism of the West that he said was siding with Kiev.

"The Ukrainian central authorities have sent the armed forces there (eastern Ukraine) and they even use ballistic missiles. Does anybody speak about it? Not a single word. And what does it mean?" "This points to the fact that you want the Ukrainian central authorities to annihilate everyone there, all of their political foes and opponents. Is that what you want? We certainly don't. And we won't let it happen."

Mr Putin once again stressed that the March annexation of Crimea was legitimate under international law, pointing to a referendum in which a majority voted to split from Ukraine.

Mr Putin initially denied that Russian troops were in Crimea but later acknowledged that they were present on the peninsula to help prevent violence after a popular uprising in Kiev ousted a Moscow-backed leader in February.