Swedish authorities said on Friday the missing information in the European arrest warrant for alleged sex crimes against WikiLeaks founder Julian Assange had been handed to British authorities.

"We sent it. They asked for complementary information and now they have it," Swedish Prosecution Authority spokeswoman Karin Rosander said.

She said she did not know whether British authorities had judged the additional information to be enough to act on the warrant. "But one has to assume they do, at least we have not heard the opposite," she added.

Sweden's highest court on Thursday refused Julian Assange permission to appeal against a European arrest order issued for alleged sexual crimes, allegations Assange has denied.

Julian Assange's British lawyer Mark Stephens told Reuters on Thursday the arrest warrant was sent back by Scotland Yard (London police headquarters), because it "did not comply with the law and was defective".

A Swedish police official said the complication had arisen because the maximum prison sentence had been listed only for the crime with the harshest punishment, while British authorities had required this to be outlined for all the alleged crimes.

It is not known where Assange is, but Britain's Independent newspaper reported on Thursday that the 39-year-old Australian was believed to be in southeast England.

Rosander said the Swedish prosecutors could not confirm Assange was in England and said it was still "unclear" what would happen if he was arrested. – Reuters