LONDON, Nov 6 (Reuters) - Siemens on Monday lost a legal challenge over a 2 billion pound ($2.48 billion) contract to build a fleet of new trains for Britain's beleaguered HS2 high-speed rail project.

Siemens Mobility sued after the contract to design, build and maintain 54 trains for HS2 was awarded to a joint venture between Bombardier Transportation – since acquired by France's Alstom – and Japan's Hitachi in 2021.

HS2 said the contract, which includes a 12-year maintenance and services deal, was worth around 2 billion pounds when it was awarded.

Siemens argued at London's High Court that HS2 unlawfully awarded the contract to the Alstom-Hitachi joint venture, including because HS2 did not verify whether the joint venture could meet the technical requirements of the project, and sought unspecified damages for losing out on the project.

But Judge Finola O'Farrell dismissed Siemens' case on Monday, saying in a written ruling that Siemens had not established the contract was awarded unlawfully and the company was therefore "not entitled to any damages".

A Siemens Mobility spokesperson said: "We are obviously disappointed with the judgment as we believed there was a significant case to answer around our strong bid to build Britain's new HS2 trains."

A HS2 spokesperson welcomed the ruling, saying the project has "a strong track record on procurement", with more than 20 billion pounds of contracts awarded to date and no successful legal challenges.

Alstom declined to comment on legal proceedings. Hitachi did not immediately respond to a request for comment.

Monday's ruling is a rare piece of good news for the controversial HS2 project, which was originally planned to link London to the north of England from 2026.

However, British Prime Minister Rishi Sunak last month cancelled the construction of the leg to Manchester, meaning HS2 will only run from London to Birmingham in central England.

The move drew widespread criticism and underlined the long delays and high costs that often beset major infrastructure investment projects in Britain. (Reporting by Sam Tobin; Editing by Kirsten Donovan)