Later today, Prime Minister David Cameron will try to persuade US President Barack Obama of the need for more cooperation between intelligence agencies and US tech firms like Twitter and Facebook.
He will say that public safety is at stake, and that new laws regarding communication via social media platforms should be imposed following the attack on Charlie Hebdo.
Cameron believes individuals posing a threat to security should not be able to send private messages without the government being able to read them.
“Are we prepared to allow in future, as technology develops, safe spaces for terrorists to communicate? The principle I think we should adopt is that we are not content for that to happen,” he said in a commons debate yesterday.
Details of how far the government wishes to take these rules are not yet clear, but the Prime Minister has already said the sites have a “social responsibility to tackle extremist content online and report suspicious activities".
It is a continuing theme – the UK government criticised Facebook in the aftermath of the murder of Lee Rigby in 2013, saying it provided a “safe haven for terrorists”.
The US has been less critical of social media companies, however. Matthew Barzun, US ambassador to the UK, said is was unfair to “pin everything on the private sector”.
The meeting of the two world leaders in Washington will be Cameron's last trip abroad before the general election in May.
Downing Street said: “The prime minister’s objective is to get US companies to co-operate more. That will be his approach in these discussions: how do we work together to get them to do so?”