David Cameron, who is in Washington to meet President Barack Obama and discuss the need to intercept internet communications and the setting up of the joint “cyber cell” to defeat cyberattacks, said there was a “broad agreement” between the US and UK.
An unprecedented amount of intelligence co-operation and information sharing between the two nations is expected to be announced at the talks reports Sky News.
The “unprecedented” arrangement between the two countries was announced as Prime Minister David Cameron held talks with US President Barack Obama.
Agents will also co-operate in “cyber cells” on both sides of the Atlantic.
Downing Street said the cells, involving MI5 and the FBI, were the first the UK had established with another country reported BBC.
They will aim to improve the flow of information between the US and UK about threats.
The Prime Minister has said: “We shouldn’t leave a safe space in which terrorists can communicate with each other.
“There is a broad agreement that we need to have powers, in extremis, to intercept communications between terrorists. That is what America does today. It is what Britain does today.
Under the plans, GCHQ and MI5 would join with the National Security Agency (NSA) and FBI to create a rolling programme of simulated war games involving attacks on the City and Wall Street to test their resilience.
It comes after a report by GCHQ warned that British companies are under attack by hackers, criminal gangs and foreign intelligence services.
Mr Obama is strengthening the US response to cyberattacks in the wake of the hack on Sony Pictures.