Deputy Nationals Leader Barnaby Joyce has bowed out of appearing on Q&A a week after three other conservatives also boycotted the show.

The news came hours after Mr Joyce told ABC’s Insiders program on Sunday that the embattled national broadcaster’s response to the appearance and backlash from Zaky Mallah’s appearance was “proper”.

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It’s an abrupt turn around, and the reasoning is still unclear, though Prime Minister Tony Abbott has reportedly forbidden his frontbenchers to appear on the program.

BREAKING: Barnaby Joyce withdraws from Q&A, saying Prime Minister Abbott has decreed no frontbenchers to appear http://t.co/83zksip3nf

— Matthew Knott (@KnottMatthew) July 5, 2015

According to Fairfax, Mr Joyce didn’t know he wasn’t allowed to appear on the show.

“The Prime Minister (Tony Abbott) has communicated that he does not want any frontbencher to appear on Q&A,” a spokesman for Mr Joyce said.

Zaky Mallah started it all with a question over how he would have been treated under the government’s citizenship laws. Photo: ABC

“Barnaby was told this tonight and apologised to Q&A that he would not be able to appear.”

This was after Mr Joyce’s appearance on Insiders, when he said: “I think the ABC is dealing properly now with the issue, I think having Mr Mallah on that program was an absurdity.

“Otherwise they’ll put fascists on and stalinists and every combination and permutation of people who have and abrupt view of the way the world works, but they are dealing with that now and it’s proper.”

Communications Minister Malcolm Turnbull is scheduled to appear on the episode of July 13, but it is not clear whether he will observe his leader’s ruling or keep his word that he wouldn’t boycott the show.

He avoided appearing last week when three conservatives – Mr Turnbull, Parliamentary Secretary to the Prime Minister Alan Tudge, and Menzies Research Centre director Nick Cater – pulled out of the show at the last minute.

On June 22, Zaky Mallah and parliamentary Secretary Steve Ciobo had an acrimonious dispute on the show over citizenship laws, which resulted in Mr Abbott saying “heads should roll” at the ABC, and Managing Director Mark Scott making a public defence of the broadcaster’s independence.