WASHINGTON/HELSINKI (Reuters) - Finland has chosen U.S. defence giant Lockheed Martin's F-35 fighters in a tender to replace ageing F/A-18 combat jets, a source familiar with the matter told Reuters on Friday.

       Lockheed Martin competed for the deal with Sweden's Saab, U.S. rival Boeing, France's Dassault and Britain's BAE Systems.

       The Finnish government said earlier it would announce its choice at a news conference later on Friday.

       The government has approved a budget of 10 billion euros for the acquisition out of which 9.4 billion euros would be used to buy the warplanes themselves.

       (Reporting by Mike Stone in Washington and Essi Lehto in Helsinki; editing by Tim Hepher)