Foreign Minister Marise Payne says Australia remains "completely opposed" to the death penalty amid fears that Australian native Julian Assange could be exposed to such punishment if he is extradited to the United States.

Australian consular officials plan to visit the WikiLeaks founder in a London jail on Friday a day after he was arrested at the Ecuadorian Embassy where he'd been holed up nearly seven years.

For now, he faces a single computer conspiracy charge in the U.S. that does not carry the death penalty, but his supporters fear more serious charges may be brought later.

Payne said Friday the U.K. had sought assurances from the U.S. that Assange would not be exposed to the death penalty.

Assange plans to fight extradition, but Australian leaders have indicated they wouldn't intervene.