A ban on sex between politicians and their staff is being suggested by independent Federal MP Cathy McGowan.

Deputy Prime Minister Barnaby Joyce has insisted on his right to privacy over his relationship with a former staff member who is now expecting his baby.

But his situation has prompted a debate about the appropriateness of relationships between politicians and their staff.

"Good workplace practice includes clear expectations about behaviour," Ms McGowan said.

She noted that United States Congress has recently dealt with the issue.

Congress recently passed a bill to address sexual harassment, which says in part that politicians may not have a sexual relationship with their staff.

US politicians would also be banned from making unwelcome sexual advances.

Ms McGowan said she is happy to begin the conversation and would potentially table a motion in Parliament.

"Good workplace practice includes clear expectations about behaviour," Cathy McGowan says. ( ABC News, file photo )

Her fellow crossbench MP Bob Katter said private lives should stay private but he also urged politicians to resist relationships with their staff.

"Not staff, please fellas, not staff," he told Sky News.

He indicated he might back the sort of motion Ms McGowan mentioned.

"You are in such an enormously influential position with staff," Mr Katter said.

"I support the spirit of it most certainly and I think maybe I will vote for it."

Foreign Minister Julie Bishop was no fan of the concept when asked about the US ban.

"The Government has no business interfering into people's personal lives and we wouldn't want to cross the line, so moral police were able to dictate what happens between consenting adults," Ms Bishop said.