Amazon Web Services has pulled whistle blower web site Wikileaks from its infrastructure-as-a-service platform following pressure from the US government.

Earlier this week, the controversial site moved its servers to AWS’s Elastic Compute (EC2) public cloud service. The move came after Wikileaks suffered a number of distributed denial of service attacks against its previous web hosting platform, Sweden-based PRQ.

Last week, Wikileaks site began the process of disclosing hundreds of thousands of confidential correspondence between overseas US diplomats and Washington DC. Information revealed so far includes revelations on Middle Eastern sentiment to Iran’s nuclear programme, China’s relationship with North Korea, and embarrassing depictions of the UK’s Prince Andrew. The leaks have caused something of a diplomatic crisis for the US.

Senior US politicians including President Barack Obama have condemned the site and called on companies to cut all commercial ties with Wikileaks.

"[Amazon’s] decision to cut off Wikileaks now is the right decision and should set the standard for other companies Wikileaks is using to distribute its illegally seized material," said Joe Lieberman, senator and chairman of the US homeland security committee. "I call on any other company or organisation that is hosting Wikileaks to immediately terminate its relationship with them."

Wikileaks responded to Amazon’s actions with the following message via micro blogging site Twitter: "Wikileaks servers at Amazon ousted. Free speech the land of the free – fine our $ are now spent to employ people in Europe."

The Wikileaks organisation is currently subject to criminal investigation in the US, while the site’s director Julian Assange is wanted by Swedish authorities for alleged rape and sexual molestation charges.

Amazon’s decision also raises questions over the influence government authorities can have on cloud computing providers. Previously, concerns have been expressed over the US Patriot Act, which stipulates cloud vendors must hand over any customer data if deemed to be in the interest of national security. This also applies to non-US headquartered organisations that store data in US-based data centres.

Update: AWS now says that it did not remove Wikileaks servers because of government pressure. The company claims that Wikileaks violated its terms of use, which says customers cannot host content that they do not own the rights to or that could cause injury or harm to a person or entity.

"It’s clear that Wikileaks doesn’t own or otherwise control all the rights to this classified content," a company spokesperson said. "It is not credible that the extraordinary volume of 250,000 classified documents that Wikileaks is publishing could have been carefully redacted in such a way as to ensure that they weren’t putting innocent people in jeopardy."