U.K. and and the United States will increase cooperation on cyber security, Prime Minister David Cameron said, by conducting simulated attacks to test the defences of organisations such as banks. "We have got hugely capable cyber defences, we have got the expertise and that is why we should combine as we are going to, set up cyber cells on both sides of the Atlantic to share information," Cameron told the BBC in an interview aired on Friday.

The cooperation between Britain's GCHQ agency and the U.S. National Security Agency (NSA) will include joint war games,
with the first exercise, a staged attack on the financial sector, will take place later this year, Downing Street said.

The measures come in the wake of the recent hacking of Sony Pictures' computers and the US military's Central Command's Twitter feed, where comments were posted promoting Islamic State (IS) militants.

In a Friday meeting with U.S. president Obama, the British leader also plans to discuss how the two countries could work more closely with big Internet companies such as Facebook and Google to monitor communications between terror suspects.