LONDON - Julian Assange family planned to distribute book, deemed ‘protest material’ by security, to Australian MPs and media as they urged government to intervene in proposed extradition of the WikiLeaks founder, writes the London Guardian.

Security staff at Parliament House in Canberra seized copies of a book about Julian Assange from his family members as they entered the building to meet MPs on Thursday, deeming it “protest material”.

Assange’s family and supporters visited parliament on Thursday to urge the Albanese government to intervene in the proposed extradition of the WikiLeaks founder from the UK to the United States.

They were carrying copies of a book on Assange’s case by Nils Melzer, the former United Nations special rapporteur on torture, which they intended to give to MPs and media.

But Assange’s brother, Gabriel Shipton, said parliament security refused to let the family take the book into the building, because they deemed it to be “protest material”.

“I was saying ‘this is ridiculous. They’re books’,” Gabriel Shipton said. “I offered to call Andrew Wilkie, who was the MP who co-chaired the Parliamentary Friends of the Bring Julian Assange Home Group. He said ‘yes, go ahead, call him, but you can’t take the books in’.”

The family was able to distribute books to MPs and media from a box already stored in Wilkie’s office, and a staffer from Wilkie’s office was able to later retrieve the seized books.

But Louise Bennet, a campaigner with the Bring Assange Home Campaign, said the actions of security were “ridiculous”.

“They were incredibly adamant that it was protest material and that it was not allowed into the building,” Bennet said.

“It just blows my mind. This is the sort of thing that we see in Trump’s America, that we criticise in China. What is our parliament afraid of that we can’t bring a book in?”

The Department of Parliamentary Services said it could not comment on “specific operational security matters”.

Gabriel Shipton attended parliament with Assange’s father, John Shipton, and other campaigners.

During their visit, they raised concerns about the lack of progress since the May election. The family urged Anthony Albanese to make the issue “non-negotiable” with the US.

Gabriel Shipton said on Friday that he was disappointed in the rhetoric from the new government, which he said had undergone a “significant change” since it won office.

He said Labor had been much more forthright in its criticism of the treatment of Assange before the election.

“They were elected on that platform, [it was] one of their promises essentially, and it’s one of the first ones that they’ve gone back on,” he said.

Albanese has said that he intends to pursue the matter diplomatically and that “not all foreign affairs is best done with the loudhailer”.