Russian officials remained adamant that Ukraine should be held legally responsible for the gas crisis in January that resulted in supplies to European countries being cut off. Bulgarian President Georgi Purvanov came no closer to receiving any concessions during the first day of his visit to Moscow.

"Any claims for any compensation should be sent to Kiev," Russian president Dmitry Medvedev told reporters after meeting his Bulgarian counterpart, Interfax news agency reported.

Bulgaria was the country affected the most by the disrupted deliveries, since all its gas comes from Russia via a pipeline that crosses Ukraine. But despite the public backlash in Bulgaria, Purvanov, who will launch the Year of Bulgaria in Russia during his trip, was far from hawkish on the issue, although in a national security speech in January he said Russia was not the dependable partner it was once believed to be.

In Moscow, Purvanov was more subdued, raising the issue of re-negotiating the current long-term deal, signed in January 2006. "We are raising the issue of compensation, seeking new strategical parameters of our relationship, including reaching an agreement of a new kind," he said, as quoted by Interfax.

Purvanov reiterated the demands to cut out the middlemen usually employed by Russia's state-owned gas monopoly Gazprom to make the delivery to its final customers. Three companies handle the deliveries to Bulgaria, of which only one is a fully-owned Gazprom subsidiary, while in the other two the Russian energy giant owns 50 per cent.

"I hope that the negotiations will result in removing [the middlemen] and the creation of a more efficient deliveries system," Purvanov said.

Russia's South Stream gas pipeline was mentioned in the press briefing after the meeting, with Purvanov saying that Bulgaria was ready to "help out" to ensure that the pipeline is built. Russia has secured principle agreements with Bulgaria, Serbia and Hungary to join the project, but the global credit crunch and falling gas prices are likely to delay construction well beyond the initial 2014 deadline.