The home secretary, Sajid Javid, has revealed he has signed a request for Julian Assange to be extradited to the US where he faces charges of computer hacking.

Speaking on BBC Radio 4’s Today programme on Thursday, Javid said: “He’s rightly behind bars. There’s an extradition request from the US that is before the courts tomorrow but yesterday I signed the extradition order and certified it and that will be going in front of the courts tomorrow.”

Javid’s decision opens the way to the court sending the WikiLeaks founder to the US. Assange faces an 18-count indictment, issued by the US Department of Justice, that includes charges under the Espionage Act. He is accused of soliciting and publishing classified information and conspiring to hack into a government computer.

Javid said: “It is a decision ultimately for the courts, but there is a very important part of it for the home secretary and I want to see justice done at all times and we’ve got a legitimate extradition request, so I’ve signed it, but the final decision is now with the courts.”