Judith Collins poses with Christopher Luxon after he refuses to rule out leadership bid

Judith Collins is taking a potential leadership threat in her stride, taking a selfie with the National candidate who refused to rule out a bid for her role.

On Sunday Newshub revealed Christopher Luxon hasn't ruled out rising to the top, even with Collins currently in his way. 

When asked if he fancied the role of Prime Minister he told Newshub "the first best step is to get to Parliament. Just take it one step at a time".

Shortly after the story broke, Collins posted a picture of herself and Luxon on Twitter saying the pair have been "mates for a long time".

"Christopher Luxon and I having a great time and very focused on election day".

Twitter users were sceptical about the picture, saying it seemed like a good example of "keep your friends close and your enemies closer".

"No circumstances under which I can see this ageing badly," said one user sarcastically while another accused the pair of "faking" having a good time together. 

"Don't turn your back on him dear" another warned.