The US government has paid at least £100m 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 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, and whether Britain's dependency on the NSA has become too great.