National MP Chris Penk will likely return to Parliament next week after being sacked from his ministerial portfolios for challenging Christopher Luxon's leadership.

Penk, a senior MP and now former minister, holds the safe National seat - Kaipara ki Mahurangi - which he will no longer contest at the election.

Paul Goldsmith, who picked up all of Penk's portfolios following last week's urgent caucus meeting, was musing running in the seat but publicly ruled it out on Sunday night.

RNZ understands Penk will continue working in his electorate and return to Parliament - likely next week - for the final two weeks of this sitting block.

Luxon won a confidence vote on Wednesday after Penk mounted a challenge against him, which he told The Post he did on his behalf and nobody else's.

On Monday Luxon told Morning Report Penk had been "working for himself" and had launched a leadership bid in caucus that failed.

There had been been some suggestions he was merely the numbers man for either Erica Stanford or Chris Bishop.

Both have denied that was the case.

Bishop said he was "pretty annoyed" at some of the rumours going around and it was "completely unfounded".

Stanford said she didn't challenge for the leadership and denied she was the "numbers guy" for Penk.