Lord Heseltine has told Theresa May she did not need to sack him for rebelling over Brexit.
He was fired from five government advisory roles after backing a House of Lords demand for a “meaningful” parliamentary vote on the Brexit deal.
In a letter to the Mrs May, The former deputy prime minister said that unlike her, he had not changed his mind having backed Remain before the referendum.
The Brexit bill has since received Royal Assent.
Lord Heseltine thanked the PM for the “kind remarks” in her letter to him, saying his role had been to offer advice that ministers were “free to accept, reject or ignore”.
He added: “You say in your letter that I will understand the necessity to end that relationship. Here we disagree.
“In the referendum campaign it was recognised that so deeply held and so divided were the views on both sides that members of the cabinet and other ministers were free to argue and vote against the government’s European policy without sanction.”
He said his vote against the government could not have delayed or denied Mrs May’s ability to trigger withdrawal talks under Article 50 of the EU treaties.
He added: “I have repeatedly said you have every right to end my relationship with the government.
“The simple fact remains that you have changed your mind since the excellent speech you made in the referendum campaign arguing that we should remain in the European Union. I have not.”
In a statement released at the time of Lord Heseltine’s sacking, the government said it had “a clearly stated and consistent position” that the Brexit bill should be passed without amendment.
The chief whip in the Lords asked Lord Heseltine to stand down because he voted against the government’s official position, it said, adding: “The government would like to warmly thank Lord Heseltine for his service.”
Heseltine to Theresa May: There was no need to sack me}