Julian Assange's mother fears for her son's wellbeing but insists governments won't be able to ignore the support growing behind his cause for much longer.

Australian-born Assange has been holed up in London's Ecuadorian embassy for more than six months to avoid being arrested and taken to Sweden to face sexual assault allegations.

He fears the move will eventually result in his extradition to the US to be prosecuted over the controversial release of secret US military and diplomatic files on his whistleblower website Wikileaks.

But his mother Christine Assange says the US government's witch hunt against her son has highlighted its efforts to suppress freedom of information and free speech in a range of areas.

She says while support for Assange continues to grow worldwide, it has become a political movement that has grown bigger than Wikileaks and threatens to have ramifications at ballot boxes, especially in Australia.

Assange will run as a senate candidate in this year's federal election under a yet-to-be-formed Wikileaks party banner and is recruiting others to stand with him.

"This has become political now," Ms Assange told AAP on Monday.

"You wouldn't believe the cross-section of people that are now supporting Julian's new party."

She said support for her son was evident in the number of people keeping a vigil outside the Ecuadorian embassy.

But Ms Assange fears the isolation in the embassy and the threats he faces if he leaves may be starting to get to him.

"Any person who is locked up under that sort of pressure without sunlight or fresh air is going to be suffering," she said.

"He's very resilient, but he is human and of course this is part of their strategy.

"They can't charge him, they've got no evidence."

Assange has not left the embassy since he sought political asylum in June.

The building is under constant police guard, with officers ordered to arrest him if he leaves.