Geoff Hoon has written to the American defence secretary expressing his concern at US protectionism in the arms industry.

Britain's defence secretary said in a letter to Donald Rumsfeld that legislation restricting the Pentagon's abilities to buy from foreign counties was "a potentially serious blow to US-UK relations".

"They would put us under pressure domestically to review our own policies and to consider whether we were prepared to continue to place significant defence contracts with US suppliers in the face of what could only be seen as a demonstrably uneven playing field," Hoon added.