Julian Assange, co-founder of WikiLeaks, announces that the whistleblowing website is suspending publishing operations to fight 'arbitrary and unlawful' financial blockades Reuters

Julian Assange, co-founder of WikiLeaks, has announced that the whistleblowing website is suspending publishing operations in order to focus on fighting a financial blockade and raise new funds.

Assange, speaking at a press conference in London on Monday, said a banking blockade had destroyed 95% of WikiLeaks' revenues.

He added that the blockade posed an existential threat to WikiLeaks and if it was not lifted by the new year the organisation would be "simply not able to continue".

The website, behind the publication of hundreds of thousands of controversial US embassy cables in late 2010 in partnership with newspapers including the Guardian and New York Times, revealed that it was running on cash reserves after "an arbitrary and unlawful financial blockade" by the Bank of America, Visa, Mastercard, PayPal and Western Union.

WikiLeaks said in a statement: "The blockade is outside of any accountable, public process. It is without democratic oversight or transparency.

"The US government itself found that there were no lawful grounds to add WikiLeaks to a US financial blockade. But the blockade of WikiLeaks by politicised US finance companies continues regardless."

Assange said donations to WikiLeaks were running at €100,000 a month in 2010, but had dropped to a monthly figure of €6,000 to €7,000 this year.

This had cost the organisation a cumulative €40m to €50m, he claimed, assuming donations had stayed at their 2010 level without the financial blockade.

Assange said WikiLeaks was facing legal cases in Denmark, Iceland, the UK and Australia, as well as an existing action in the EU.

He is also fighting extradition from the UK to Sweden to answer allegations of sexual misconduct.

The Guardian, New York Times, El País, Der Spiegel and Le Monde worked with WikiLeaks in publishing carefully selected and redacted US embassy cables in December, but have since criticised the website's decision to publish its full archive of 251,000 unredacted documents in early September.

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