National MP Jami-Lee Ross appears hell-bent on retribution, as he faces the boot from caucus.

The Botany MP and seventh-ranked member of National's line up, has been accused of leaking Simon Bridges' travel expenses, a claim he strongly denies.

Former National Party press secretary Ben Thomas told Mike Hosking he has no doubt about Ross's fate today.

"Jami-Lee Ross is burnt toast, he is probably on a five or six setting toast, that someone has forgotten about, that is smoking in the kitchen."

He said Ross' tweets have alienated him from any sympathy from the wider caucus.

"This isn't going to be a referendum on Simon Bridges this is just going to be about Jami-Lee Ross' conduct." 

Thomas said Nationa could invoke the Waka-Jumping legislation to get rid of Ross.

"I don't think National will have too many qualms about using it to cut out a problem."

The leak investigation found Jami-Lee Ross was the leaker, however, Ben Thomas says there should never have been an investigation.

"Probability suggested it was always somebody within the National Party camp, and it is fair to say it has probably been mishandled at every turn."

Former Labour Party president Mike Williams agrees, telling Mike Hosking the whole situation is out of control.

"This matter should never have been pursued in the first place but I think Simon Bridges needs to be very careful because, you will always have in a caucus of that size, someone going off the rails."

He said Bridges need to sort this out as quickly as possible.

"You can't welcome him back...after what he said. If you expel him, you risk a byelection because of the Waka-Jumping Bill, there's no good answer." 

LISTEN ABOVE AS BEN THOMAS AND MIKE WILLIAMS SPEAK WITH MIKE HOSKING