Feb 20 Poland's defence ministry has started on Monday tender negotiations with three firms to buy eight helicopters for special forces and a further eight anti-submarine choppers, the ministry said in a statement.

Earlier, Defence Minister Antoni Macierewicz said that Poland is considering buying the helicopters from Airbus, Lockheed Martin's Sikorsky subsidiary or Leonardo-Finmeccanica this year.

The ministry also said in the statement on its website that it has sent an "invitation" letters to Boeing as well as Lufthansa and Glomex to submit supply offers of three medium-range aircraft for the transportation of top government officials.