Bulgaria Air airline is interested in operating Sofia Airport's terminal 1 on a concession agreement, it said in a letter to the facility's management.The carrier, a subsidiary of Bulgarian Aviation Group, which is controlled by local industrial conglomerate Chimimport, seems to be the most serious prospective concessionaire at this stage."We have expressed our desire to operate the terminal on a lease of concession agreement but it's up to the airport to make the decision," Bulgaria Air executive director Dimitar Pavlov said.Airport management said the talks are still in an early stage."We are holding talks about joint use, lease or concession of the terminal," airport executive director Plamen Stanchev said.Under one of the ideas, the airport will team up with Bulgaria Air to jointly operate the facility.The terminal is currently being used by no-frills and charter airlines. Last year it handled 600 000 passengers. This number is expected to grow to 800 000 in 2009.Bulgaria's Deputy Transport Minister Yudjel Atila confirmed to Dnevnik that there is investor interest and the airport could be operated under concession.But Atila doubted that a deal would be signed under the current government, whose term expires in July.He said that candidates are interested in concessions longer than five years, which would be impossible under current legislation. Before the concession procedure could be opened, amendments should be made to the Civil Aviation Act, and a bill has already been introduced by Radoslav Ilievski of Coalition for Bulgaria.Yordan Mirchev, who chairs the government's transport committee, said the changes are unlikely to be voted during the term of the present Cabinet because they were not a priority.Interest to operate Sofia airport has also been expressed by an unnamed US company and French firm Bombardier. The candidates are seeking contracts of more than 10 years to be able to recoup their investment.Last year the Transport Ministry proposed changes to the State Property Act, which were approved by the Cabinet but were torpedoed by Parliament.