Former Bulgarian President Georgi Parvanov defended Saturday what he claimed to have contributed to Bulgaria's energy policy in response to criticims by PM Boyko Borisov.

"The records of my energy endeavors are so extensive that the PM cannot manage to read them through in one day," quipped an angry Parvanov.

In particular, he claimed merit for negotiating large quantities of natural gas from Azerbaijan to be delivered in the coming years to Bulgaria via Turkey and over the Black Sea.

Over the week, PM Boyko Borisov was on a round-trip in the Caucasus region, including a visit to Azerbaijan to negotiate further details on the natural gas deliveries.

"It was I who guaranteed Bulgaria's participation in the South Stream natural gas project, together with Vladimir Putin," went on Parvanov.

Of late, PM Borisov's cabinet has been giving positive opinions about the future of South Stream, a project regarding which it had been ambivalent in the past.

Parvanov, who acted as Bulgaria's president from 2002 until January 2012, was also critical of the Borisov cabinet's decision to give up the Belene NPP project.

He commended the decision by the Bulgarian Socialist Party to table a no-confidence vote on the cabinet regarding the matter, but added that the opposition must go further to defend the Belene NPP project.