Assange's mum defends 'highly ethical' son

Rape allegations against WikiLeaks editor-in-chief Julian Assange are a set-up, his Australian mother says.

"I know for a fact he wouldn't rape anybody, it was a set-up," Christine Assange told Brisbane newspaper The Courier Mail.

Interpol yesterday issued a global arrest warrant for the 39-year-old Australian founder of the WikiLeaks website, as the chaos from its massive dump of secret US cables spread from governments to financial markets.

He is wanted in Sweden for questioning over the alleged rape and molestation of two women. He denies the charges.

Ms Assange moved to Queensland's Sunshine Coast five weeks ago. She now operates a puppet theatre in Noosa.

She said her son had distanced himself from the family for their own safety.

"I'm concerned it's gotten too big and the forces that he's challenging are too big," she told the newspaper.

She said her son was a highly ethical person and had always been a "seeker of truth".

"He sees what he's doing as doing a good thing in the world, fighting baddies if you like."

She said Mr Assange was a highly intelligent child, who himself became a father to son Daniel, now 21, at the age of 18.

She said the way he dealt with fatherhood at an early age was a measure of his character.

"Jules put his life and university studies on hold to parent Daniel and be there for him," Ms Assange said.

- AAP