The British government on Friday approved the extradition of WikiLeaks' founder Julian Assange to the United States to face criminal charges.
The government said Friday that home secretary Priti Patel had signed the extradition order, bringing Assange's long-running legal saga closer to a conclusion.
This follows a British court ruling that he could be sent to the US.
"On 17 June, following consideration by both the Magistrates Court and High Court, the extradition of Mr Julian Assange to the US was ordered. Mr Assange retains the normal 14-day right to appeal," the home office said in a statement.
Following this, Wikileaks said Assange would appeal his extradition.
"Today is not the end of the fight. It is only the beginning of a new legal battle. We will appeal through the legal system," a statement posted on the Wikileaks Twitter accounts said.
It also said that the order marks a “dark day" for press freedom. "This is a dark day for Press freedom and for British democracy," the group said, insisting Assange, 50, "did nothing wrong" and was "being punished for doing his job".
Originally, a British judge ruled that Assange should not be deported, saying his mental health problems meant he would be at risk of suicide if convicted and held in a maximum-security prison.
But this was overturned on an appeal after the United States gave a package of assurances, including a pledge he could be transferred to Australia to serve any sentence.
Assange is wanted by US authorities on 18 counts, including a spying charge, relating to WikiLeaks' release of vast troves of confidential US military records and diplomatic cables which they said had put lives in danger.
His supporters say he is an anti-establishment hero who has been victimised because he exposed US wrongdoing in conflicts in Afghanistan and Iraq, and that his prosecution is a politically-motivated assault on journalism and free speech.