Bulgaria should host a Russian pipeline to avoid becoming a "periphery" in the energy sector, President (2002-2012) Georgi Parvanov said on Thursday.

He told the Bulgarian National Radio that that high-level Bulgarian officials should pay a visit to Moscow to "come to an agreement" on such a project. "This doesn't contravene European interests, nor does it contravene our civilizational choices... This pipeline has to pass through Bulgaria, because otherwise [we would] remain a periphery."

Parvanov commented amid uncertainty over whether he is to seek a third term in office in the presidential elections this autumn. A day earlier he stopped short of announcing his intentions.

During his two terms, he initiated three major energy projects with Russia which were all later abandoned either by either the Bulgarian or the Russian government.

His remarks on the Russian pipeline also follow publications in Russian media suggesting a new Russian pipeline supplying Greece would have to use Bulgaria as a transit country.

In March, Gazprom signed a Memorandum of Understanding with Greece's DEPA and Italy's Edison on the delivery of gas to the two respective countries, but "via third countries". With tensions between Russia and Turkey still flaring, Bulgaria could be the only transit option.

Russian President Vladimir Putin is meanwhile visiting Greece on Friday to discuss possible joint projects in energy and transport with Greek Prime Minister Alexis Tsipras. Russian media outlets has suggested the issue of "reviving" the abandoned South Stream pipeline via Greece might also be raised during their talks.

Earlier in May, the US' high energy envoy Amos Hochstein warned after an energy summit with EU officials that any gas projects other than the Trans-Adriatic Pipeline (TAP), interconnectors and LNG terminals would be a "distraction" from common energy goals.