(CNN) -- WikiLeaks, beset by technical problems regarding its website and under fire from governments worldwide, has now lost a major revenue source.
Payment service provider PayPal cut WikiLeaks' online donation account Friday.
WikiLeaks violated its acceptable use policy, "which states that our payment service cannot be used for any activities that encourage, promote, facilitate or instruct others to engage in illegal activity," PayPal said in a statement.
WikiLeaks, which confirmed the change Saturday, said on its Twitter page that the action was based on U.S. pressure.
The tweet sends readers to a donation page, where supporters can pay by credit card, bank transfer or through the mail. The page also solicits for a defense fund for founder Julian Assange.
Assange's whereabouts have been undisclosed since WikiLeaks began publishing 250,000 confidential U.S. diplomatic cables earlier this week. He is wanted by authorities in Sweden on unrelated allegations of sex crimes, including rape.
Assange has denied the accusations, calling them a smear campaign.
WikiLeaks posted an article on PayPal's move on its Facebook page. More than 2,400 people, many upset with PayPal's decision, left comments Saturday.
A U.S.-based domain name provider shut down WikiLeaks early Friday, but the controversial website announced hours later that it had employed a company in Switzerland and was back up. Amazon also kicked the site off its servers.