Nadine Dorries should apologise to the House of Commons and register how much money she made from appearing on I'm A Celebrity Get Me Out Of Here, a committee of MPs has decided.
The outspoken Tory MP had refused to declare to the parliamentary commissioner for standards how much she earned from the reality show because of a confidentiality agreement with ITV.
But on Monday the House of Commons Standards Committee found Dorries had failed to abide by the registrar's advice and had breached the code through her "attitude to the Commissioner's inquiries".
The committee recommended that Dorries registers all payments in respect of her employment and "apologises to the House by way of a personal statement".
Dorries lost the Conservative Party whip in 2012 after agreeing to appear on the programme. The Mid Bedfordshire MP was only allowed to sit as a Tory MP again earlier this year.
Standards Commissioner Kathryn Hudson found that the payments made to Dorries as a result of her appearance on the show should have been declared.
The committee's report said: "Ms Dorries contended that such payments (if any) were made to a company, Averbrook Ltd, of which she is a director, and that she was not required to register income received by the company, but only any remuneration she drew from it.
"Ms Dorries further contends that as she was not required to register the company's income, she did not have to respond to the Commissioner's requests for information about payments from her media work."
The report said that, while her media work may not have influenced her representation of her Mid Bedfordshire seat, it was "likely to have been linked to her work in the House".
It added: "We find it hard to believe she would have been invited to appear on I'm a Celebrity if she had not come to public prominence as a Member of the House.
"It is clear that Ms Dorries's media work was remunerated, whether or not those payments were made to her or to her company.
"We agree with the Commissioner that Ms Dorries should have registered payments for such media services even though those payments were made through Averbrook Ltd."
Dorries told the Committee that if she disclosed how much she had been paid by ITV she would "fall foul" of the contract's confidentiality clause.
But the committee said the House's rights to information "cannot be overridden by confidentiality agreements" and added: "In any event, Ms Dorries should not have signed a contract which required her to keep confidential matters which should have been registered."
Dorries updated her entry on the register of MPs' interests at the end of October, covering the previous 12 months.
It showed Averbrook's gross income was £142,000, giving a profit of £82,000, and that Dorries had taken a £10,000 dividend on October 30.
She spent approximately 60 days working on Averbrook's projects, which were described as "writing and media appearances".
In its conclusion the committee said: "Ms Dorries must register the details required by the rules. That leaves her initial failure to abide by the registrar's advice, and her attitude toward the Commissioner's inquiry.
"The House's Code of Conduct and disciplinary system depend on Members being prepared to explain their conduct, to submit to public scrutiny and where necessary, to respond to the Commissioner's inquiries."
The committee said Ms Dorries should consult the registrar within 21 days about the detail of her entry on the register.
"We will monitor Ms Dorries's compliance and will recommend further action if necessary," the report said.