UK Home Secretary Shabana Mahmood has restricted migration minister Mike Tapp's access to sensitive documents and meetings without her approval, as she called for the prime minister to sack him. This was reported by Qazaqyia.kz citing The Guardian.

Mahmood demanded Tapp be fired for writing an unauthorised article in The Times calling for overseas care workers to be exempt from changes to immigration rules.

Downing Street said Tapp – a loyal supporter of Keir Starmer – remained a minister but that the prime minister was taking advice on whether he broke the ministerial code on collective responsibility.

The public row between Tapp and Mahmood escalated on Friday, with the junior minister saying he would not be "intimidated". In a sign of the breakdown of ministerial discipline in the last days of Starmer's time as prime minister, Tapp, the MP for Dover, delivered a defiant response on his X account to Mahmood's call for him to be sacked.

In a tweet he appears to have deleted, Tapp responded to a supporter: "The attempted intimidation is quite a sight. I've seen off the Taliban and taken out terrorists. Country first, always." He later apologised "wholeheartedly" for the "poorly judged tweet", adding: "I have a lot of respect for the Home Secretary and will continue working hard for our country."

In an earlier post, he said: "Ok, morning all. It's gone from 'he broke the ministerial code' to 'he stole my idea'. I have put my views across on a policy I've been working on for months (I have the receipts) in an Op Ed in the Times. Give it a read, and let's continue to discuss."

A Home Office source claimed Tapp had taken proposals Mahmood had been working on and briefed them as his own. One source said: "Mike Tapp wrote a piece in a national newspaper freelancing on policy without the knowledge or agreement of the home secretary or her team. He took proposals that the home secretary was working on, and briefed them as his own. In doing so, he has broken collective responsibility and has breached the ministerial code. Now he is threatening to leak sensitive documents. The home secretary has asked the prime minister to sack him."

Pressure is building on Starmer to act after another member of the government said it was "unwise" for junior ministers to set out views in the way Tapp had done. The prime minister's official spokesperson told reporters that Starmer was "taking advice in the usual way". The Cabinet Office's propriety and ethics team (PET) is understood to be one source who could be providing that advice.

Later, a Downing Street spokesperson said Tapp had been "reminded of his obligations under the ministerial code", but added: "It is not for any individual secretary of state to determine whether the ministerial code has been followed, it is a matter for the prime minister alone."

Tapp wrote in The Times that it was his "strong belief" that migrant care workers should not have to wait longer to apply for permanent settlement in the UK. Mahmood was unaware he had written the article, which a source close to her claimed had been done "to try to win a job in the new administration".

The justice minister, Jake Richards, told Times Radio that the Home Office needed to "take a deep breath". He said: "Mike's article in The Times sets out what his views are and some of the issues that he in the Home Office is exploring. It's not particularly wise in my mind for junior ministers to kind of set that out publicly. We are part of a team, but he has done that and we will deal with that as a government."