NSA pays British spy agency for access and influence

The US government has paid at least £100 million (HK$1.17 billion) to the UK spy agency GCHQ over the last three years to secure access to and influence over Britain's intelligence gathering programmes.

The top secret payments are set out in documents which make clear that the Americans expect a return on the investment, and that GCHQ - Government Communications Headquarters in Cheltenham, southwest England - has to work hard to meet their demands.

"GCHQ must pull its weight and be seen to pull its weight," a GCHQ strategy briefing said.

The funding underlines the closeness of the relationship between GCHQ and its US equivalent, the National Security Agency. But it will raise fears about the hold Washington has over the UK's biggest and most important intelligence agency.

In one revealing document from 2010, GCHQ acknowledged that the US had "raised a number of issues with regards to meeting NSA's minimum expectations". It said GCHQ "still remains short of the full NSA ask".

Ministers have denied that GCHQ does the NSA's "dirty work", but in the documents GCHQ describes Britain's surveillance laws and regulatory regime as a "selling point" for the Americans.