Canberra, Feb 15 (IANS): Australian Prime Minister Malcolm Turnbull on Thursday announced a ban on sexual relationships between ministers and staffers, a measure taken after a scandal involving his deputy rocked the nation.

Turnbull condemned Barnaby Joyce for a "shocking error of judgment" over an affair with his former media adviser Vikki Campion, with whom he is expecting a child, the BBC reported.

"I have today added to the standards to make a very clear and unequivocal provision that ministers, regardless of whether they are married or single, must not engage in sexual relations with staff. Doing so will constitute a breach of the standards," said the Prime Minister.

Joyce will take a leave of absence from Monday amid scrutiny over whether he breached ministerial standards.

Turnbull earlier told Parliament that Joyce would not fill his post as acting leader next week when the Prime Minister travels to the US.

The scandal has dominated Australian politics since last Wednesday when Joyce's affair with media adviser Vikki Campion was publicly revealed.

Opposition parties called on him to resign. The high-profile conservative had only returned to Parliament in December after briefly losing his job over his New Zealand dual citizenship.

Turnbull said his deputy had caused "terrible hurt and humiliation" to his estranged wife, Natalie Joyce, their four daughters, and Campion.

"Barnaby... has set off a world of woe for those women and appalled all of us. Our hearts go out to them."

On Tuesday, Joyce publicly apologised to all six for what he called a "searing personal experience".

Turnbull said such behaviour was not acceptable "today, in 2018", and ministers must oversee respectful workplaces.