Barnaby Joyce has confirmed his baby boy has not yet been born.

Joyce stood down as deputy prime minister and leader of the Nationals Party in late February amid sexual harassment allegations that followed revelations he was having a child with his former staffer, Vikki Campion.

Ms Campion, who he has since formally registered as his partner, was rumoured to be expecting in April – something 7.30 Report presenter Leigh Sales could not resist mentioning during an interview about coal power on the ABC.

"Quickly, before you go, it was reported your baby was due in April. Has he arrived yet?" Sales probed.

Joyce took a long look off camera to his right and replied with one word. “No”.

Both Joyce and Sales then laughed.

Sales had earlier asked about the state of his relationship with the prime minister, which appeared to be in tatters after Turnbull claimed he made a "shocking error of judgement" by having an affair.

Joyce said the Coalition would lose the next poll, but backed Turnbull to take the Liberal Party to victory at the next election.

"I'm absolutely certain Malcolm can do it. It's not about for me changing Malcolm Turnbull," he told the 7.30 Report.

"This is about trying to make sure that the people that we represent, especially here in the National Party, get affordable and reliable power."

When asked about the last time they spoke, Joyce said: "He left me a message tonight."

"And prior to that, when did you last speak to him?" Sales asked.

"Can't remember. Look, I get along with Malcolm. There's not an issue with Malcolm. This is an issue for me to try and represent our people, my people and that's exactly what I'm doing here."

© Nine Digital Pty Ltd 2018