Pentagon officials got something of a fright when a Ministry of Defence laptops was stolen last May.
The Guardian has obtained a ministerial letter in which the British government responded to a complaint from the US about security procedures in Britain.
In it, the government gave assurances that security in the UK would be tightened up.
The paper quotes sections of the letter, from Baroness Symons, minister for defence procurement, to her opposite number in the Pentagon. In it, she promises that she had "made sure that your concerns on the joint strike fighter laptop incident are acted upon."
The notebook computer was stolen from a luggage rack on a train in Paddington Station, and contained details of a collaborative project to develop a swanky new fighter jet between governments of the US and the UK.
It was taken by an opportunistic thief, the government said at the time, and surfaced when the fence it had been sold to tried to sell the contents of the hard drive to the tabloid press.
In response to the complaint from the US, government employees were told to carry laptops less conspicuously when travelling on public transport.
The theft in May was one of a string of incidents of government employees losing laptops containing sensitive information last spring. The most memorable was the case of the secret services employee who left his notebook in a cab, after going out on the piss. ®