John Bercow faces a fight to hold his position as Speaker of the House of Commons in the wake of his comments about Donald Trump.
Tory MP James Duddridge has tabled a parliamentary motion of no-confidence in Bercow, who told MPs earlier this week that Mr Trump would not be allowed to address the Commons during his state visit.
Duddridge predicted Bercow, the MP for Buckingham, could be "dead in the water" if lawmakers made their concerns about him known.
Fellow Tory MP Alec Shelbrooke backed the move, saying Bercow had "politicised the office of Speaker and his position is untenable".
However, the motion has caused Bercow’s supporters to rally behind him.
Labour MP Jess Phillips said: "Loads of Tories don't like Bercow because he's trying to reform the Commons and make it more representative.
"I will vote to support John Bercow, and it's utterly ridiculous and self-indulgent of MPs who will waste all our time on this."