MOSCOW (Reuters) - Russia signalled on Wednesday that it could toughen demands for gas payments from Ukraine if Kiev fails to fulfil existing agreements, adding to pressure on an ex-Soviet neighbour gripped by an economic and political crisis.
Moscow is concerned about Ukraine's growing debt for gas but will not review deals as long as Kiev meets its obligations, Russian President Vladimir Putin's spokesman, Dmitry Peskov, said on Kommersant-FM radio.
