Nadine Dorries faces being blocked from joining the House of Lords over claims she misled MPs.
The ex-culture secretary is in line for a peerage from Boris Johnson as a reward for being his biggest cheerleader.
But the Commons culture, media and sport select committee will hold urgent talks this week on whether her elevation to the Lords should be stopped.
It will make a decision as soon as Tuesday on whether the ex-minister should be referred for a Commons investigation into allegations she misled them over a Channel 4 programme she took part in.
At a hearing earlier this year, she claimed the 2010 reality show Tower Block of Commons used paid actors to play supposedly real people.
But she has been asked to back up or retract her remarks after an investigation by the broadcaster found no evidence of fakery.
The committee will decide on next steps this week after Mrs Dorries ignored its requests for her to clear up the confusion.
If a Commons investigation finds she misled MPs, this could block her path to the Lords.
A source on the committee said: “The Lords don’t particularly want her. This could be the thing that actually stops her.
“Even though it may seem like it would be a minor untruth to Parliament, it would be a serious enough matter for them to say ‘we are sorry you are not getting a peerage’.”
On the reality show, Mrs Dorries was sent to live in an estate in South Acton, west London. In May, she told Parliament she believed the family who hosted her were planted by the show’s producers.
“I discovered later they were actually actors,” she told MPs. “The parents of the boys in that programme actually came here to have lunch with me, and contacted me to tell me, actually, they were in acting school, and that they weren’t really living in a flat, and they weren’t real.
“And even, if you remember, there’s a pharmacist or somebody that I went to see who prepared food – she was also a paid actress as well.”
After a Channel 4 review found no evidence for her claims, Julian Knight, the chair of the Commons culture, media and sport select committee asked Mrs Dorries for a response to the findings of the investigation “as a matter of urgency”.
The former culture secretary has been one of the staunchest defenders of Mr Johnson.
Yesterday when asked if he could return as prime minister, she told the BBC's Sunday with Laura Kuenssberg: "I have been in politics a long time, I don't rule anything out. But I would say it is highly, extremely unlikely."
