The decision on whether to approve the extradition now rests with British Home Secretary Priti Patel, although Assange's lawyers may still appeal within 14 days against any decision that approves the extradition.
"In layman's terms, I am duty bound to send your case to the Secretary of State for a decision," said chief magistrate Paul Goldspring after he issued the extradition order.
Last month, Britain's Supreme Court denied Assange permission to appeal against a High Court decision to extradite him to the United States.
"The UK has no obligation to extradite Julian to USA, in fact it is required by its international obligations to stop this extradition." @StellaMoris1 statement after UK Court issued an order to extradite WikiLeaks founder Julian Assange.pic.twitter.com/9SACo6TifN@telesurenglish
Assange is wanted in the United States on allegations of disclosing national defense information following WikiLeaks's publication of hundreds of thousands of leaked military documents relating to the Afghanistan and Iraq wars a decade ago.
The 50-year-old journalist has been held at south London's high-security Belmarsh Prison since 2019. He married his long-term partner Stella Moris, a lawyer, in the prison last month.
"The U.S. request to extradite Assange from Britain is politically motivated. The U.S. extradition request for Assange is retaliation in disguise, and this constitutes yet another example of the United States encroaching on other countries' sovereignty," Moris said.
"The U.S. is abusing its real power, its ability to get others to do what it wants because of its might, in order to silence him, because he has embarrassed parts of the U.S," she added.