Mr Broad decided on Tuesday not to re-contest his northern Victorian safe seat of Mallee, following revelations he travelled to Hong Kong and dined with a younger woman he met online, charging taxpayers for the domestic leg of the trip.

Mr McCormack says Mr Broad showed a "complete lack of discretion" but has stressed he is just one individual in a hard-working team.

"I'd like to think there's not going to be long-term damage," the deputy prime minister told AAP on Wednesday.

"I'd like to think that going forward, not just my colleagues, but indeed the general public, would like to think that the National Party are working hard for them."

Asked whether he believes there is a need to reiterate the party's values, Mr McCormack was straightforward.

"Quite frankly, I don't think you can teach common sense," he said.

"I'm amazed that they have time to be able to do these sorts of things, let alone actually then have the lack of discretion to go and do them."

The Nationals leader said he is "disappointed and disgusted" by the matter but that it's now time to move on, with a renewal and refocus.

Details about the Hong Kong meeting between the woman, named as "Amy", and the married Mr Broad, 43, surfaced in New Idea magazine this week.

She told the magazine he had lied about his age, sent her numerous text messages that turned to a "more sexual nature" following the dinner, and compared himself to "James Bond".

Mr Broad on Tuesday agreed to pay back $479.62 for domestic flights between Mildura and Melbourne, on September 2 and 7, which were part of the overall trip to Hong Kong.

"After recent media stories about my private life, it is clear that the people of Mallee will be best served in the next parliament by a different Nationals candidate," he said in a statement on Tuesday.

AAP understands Mr Broad will stay on in federal parliament representing the Nationals until the election, due in May, and won't switch to the crossbench to sit as an independent.

Focus has now turned to who the Nationals will put up in the safe seat, won in 2016 with a margin of more than 20 per cent.

Deputy Nationals leader Bridget McKenzie could be a potential candidate.

Mr McCormack said he's looking forward to speaking with Senator McKenzie later on Wednesday.

But the Nationals usually put "local champions" into seats, he stressed.

"We don't necessarily parachute candidates."

Australian Associated Press