Former Baywatch star Pamela Anderson has received a letter from the Prime Minister Scott Morrison, rejecting her passionate plea for Australia to help Julian Assange.

The WikiLeaks founder is behind bars in Britain as he fights a US extradition bid on charges filed under the espionage act.

He faces a sentence of up to 175 years in an American prison.

Anderson has been publicly urging Mr Morrison to appeal to British and American authorities to free Assange, declaring he is innocent.

But in a letter to Anderson, published by News Corp, the Prime Minister said the federal government could not intervene in the legal proceedings.

“The Australian government continues to monitor Mr Assange’s case closely, as it would for any other Australian citizen in detention overseas,” the letter says.

“Beyond providing consular assistance, it is important to note that Australia has no standing and is unable to intervene in Mr Assange’s legal proceedings.”

Assange facing ‘psychological torture’, Anderson says

Anderson has been a vocal supporter of the 48-year-old, visiting him in prison in May and at the Ecuadorian embassy in London on several occasions.

She was reportedly due to give a speech at Parliament House this week, but cancelled due to a scheduling conflict.

But in a post on her website to the Prime Minister and Foreign Minister Marise Payne, titled: “From Pamela to Australia” she declares Assange is facing “psychological torture”.

“I make a heartfelt personal plea to every parliamentarian that is charged with the responsibility to uphold the protection of the citizens of Australia to now stand and protect Julian Assange by initiating contact with your counterparts in the USA and Britain and demand no extradition,” she said.

“Allowing him to return to his home and hug his mother, father and his children.

“This will in turn also uphold the sovereign rights of your citizens which is the highest order of an elected parliamentarian.”

-ABC