Bulgarian Prime Minister Boyko Borisov on Monday called on Brussels and Moscow to sit at the table with Sofia officials and discuss the prospects ot carry out a gas hub project on Bulgarian territory.

His comments came as Bulgaria was hosting a conference promoting options to set up a gas distribution center, with dozens of potential investors and representatives of gas companies being invited.

Russian officials are not attending the event.

Russi has no "perspectives" and no potential gains from the project as of the moment and was therefore not invited, Borisov noted.

But the Bulgarian National Radio quoted him as telling as he was opening the conference:

"The European Commission are obliged to give us back the gesture, not just to give us optimisim."

Brussels has been welcoming the gas hub project in principle, but has not included it in the list of priority projects.

Russia, on the other hand, has raised skepticism about the deal, questioning the diversity of gas sources.

The event was organized by state-owned Bulgartransgaz, the country's gas grid operator.

Four options to create the so-called Balkan Gas Hub were unveiled by Bulgartransgaz last week, but that was their first introduction to investors.

The different possible business models of the project would result in a cost between EUR 1.2 B and EUR 2 B.

Balkan Gas Hub was first put forward short after the demise of South Stream, a pipeline project that would have transited Russian gas to Central Europe via Bulgaria but was abandoned by Moscow which cited EU opposition.

Borisov insisted a tripartite Bulgaria-EU-Russia meeting should be held, and a Brussels official should attend all talks dedicated to the Balkan Gas Hub once the project is launched.

"We want a EU commission representative in all negotiations so that we know there won't be an infringement procedure notice in two or three months," he made clear.

It was the EU's warning of a possible infringement procedure that put an end to South Stream in December 2014.

However, with Bulgaria still hoping to host a Russian pipeline, Borisov added: 

"If Europe needs Russian gas to come to the Balkan Gas Hub, this should be stated and I will then send a minister to negotiate the conditions."

"They [Russia] are holding their pipes in Varna and Burgas, waiting for a European decision... When we go to Moscow, we should say: This is the decision of Europe, not only of Bulgaria, but of the entire European Union. This is when talks can begin."