Barnaby Joyce, who left his wife after having an affair with a staffer, wants the coalition to overturn a ban on federal MPs hiring family members to work for them.
But neither the government or the Labor Party intend to change the rules.
Former prime minister Tony Abbott in 2013 decided relatives could no longer work for MPs or senators, in a bid to head off claims of nepotism.
But Mr Joyce says that was a mistake.
“(Your loved one is) probably one of the best persons working for you because she more than anyone understands your diary, understands kids’ birthdays, anniversaries. Understands all the things you’ve got to be a part of if you want to stay married,” he told The Courier-Mail in an interview published on Friday.
Mr Joyce resigned as deputy prime minister and Nationals leader this year after it was revealed he had an affair and had left his wife and three daughters.
Prime Minister Scott Morrison ruled out dumping the ban.
“I have no plans to do that. That arrangement has been in place for five years,” he told Seven Network.
Labor leader Bill Shorten echoed his statement.
“Labor has no plans to change the existing policies,” he told reporters in Canberra on Friday.