MOSCOW (AFP) - President Vladimir Putin's spokesman said Wednesday that Russia was increasingly concerned about Ukraine's growing debt on its gas payments and needed an explanation about its future policies in the face of pro-EU protests.

"We are concerned about the growing debt for gas deliveries," Putin's spokesman Dmitry Peskov said in a radio interview, adding that further payments on a Russian bailout package will be release when "the new Ukrainian head of government is able to explain to Moscow how much he intends to keep to the previously-declared (political) course."