"First of all, I am very pleased that the police were able to seize him and now he is right behind bars because he broke British law," Javid told BBC Radio 4 on Thursday.
"There is an extradition request from the United States that is in court tomorrow, but yesterday I signed the extradition order and confirmed it, and it is going to go to court tomorrow," he added.
The United States will detail all charges against Assange on Friday when seeking its extradition in a London court.
The US prosecutors originally accused Assange of a single number of computer intrusions, but last month, 1
Such a tax under the espionage law has never been prosecuted, according to CNN's legal analyst Steve Vladeck.
Assanges original charge triggered a debate on the first amendment, and whether his alleged role in purchasing secret US material constituted protected journalistic activity.
Assange lived in the Ecuadorian embassy in London for seven years to April when the country revoked its protection and he was arrested.
United Kingdom Home Office said in a statement: "Assange was arrested in connection with a provisional extradition request from the United States. He is accused of offenses including abuse of computers and unauthorized disclosure of national defense information."  "We have received full extradition request, which has been certified by the home secretary.
" This case is now for the courts and it would be inappropriate to comment further. "