Six Greek ministers and two deputy ministers are attending an intergovernmental meeting with Bulgarian cabinet members in Sofia alongside the two countries' prime ministers on Monday.

Greece's PM Alexis Tsipras is on a visit to Bulgaria on Monday.

Apart from energy issues, where the two countries are pursuing joint projects, migration and increased pressure on both countries' borders with Turkey are thought to be key issues on the agenda of the joint cabinet meeting.

Bulgaria has shown interest in a project to build a liquefied natural gas (LNG) terminal in the Greek port city of Alexandroupoli, and a joint venture could be set up to this end if talks are successful. Sofia and Athens also hope for the Interconnector Greece-Bulgaria (IGB), a vital gas link between the two countries, to be ready within a few years.

Daily newspaper 24 Chasa cites "sources" who say funding for the LNG terminal could be secured either through a joint venture between state-owned entities or by leaving the door open to private companies from either or both countries.

The prospects for energy cooperation come as Bulgaria seeks to build a "gas hub" and transit gas from sources such as the prospective Trans-Adriatic Pipeline (TAP) and, possibly, from Iran (via the LNG terminal and IGB once they are in place) and reduce dependence on Russia as its biggest gas source.

A joint declaration of Boyko Borisov and Alexis Tsipras will be among the bilateral documents to be signed as the Greek officials are visiting the country.