Johnny Mercer has been sacked as minister for veterans following reports he intended to resign over ongoing prosecutions against British soldiers who served in Northern Ireland during the Troubles.
A Downing Street spokeswoman said last night: "This evening the prime minister has accepted the resignation of Johnny Mercer as Minister for Defence People and Veterans.
"He thanks Johnny Mercer for his service as a Government Minister since 2019."
However, Mr Mercer suggested he had been sacked.
He tweeted that he was "sorry to have been relieved of my responsibilities in government tonight".
Mr Mercer was critical that former British soldiers were being investigated for killings during the Troubles.
It is thought he was particularly unhappy at the trial of two former paratroopers accused of the 1972 murder of Official IRA man Joe McCann.
The soldiers, now in their seventies, are to be tried at Belfast Crown Court.
Their identities are to remain secret during the trial.
In a letter to the prime minister, posted on his Twitter account, Mr Mercer said elderly veterans had been asked "to relive, through endless reinvestigations and inquests, into events often more than fifty years ago in Northern Ireland".
He added: "Whilst endless plans are promised and solutions mused, veterans are being sectioned, drinking themselves to death and dying well before their time - simply because the UK Government cannot find the moral strength or courage we asked of them in bringing peace to Northern Ireland, in finding a political solution to stop these appalling injustices."
Mr Mercer said he had hoped Mr Johnson's premiership would "signal a step change in veterans affairs in the UK".
He added: "Whilst we continue to say all the right things, you will understand that if we fail to match that with what we deliver, we risk damaging an already bruised veterans cohort further, as I told you last month in our first face to face meeting, we crossed that line some time ago."
Mr Mercer had been heavily involved in the Overseas Operations (Service Personnel and Veterans) Bill, which is going through its final stages in Parliament.
The legislation was developed in response to legal claims made after operations in Iraq and Afghanistan but it does not cover incidents in Northern Ireland.
Lords amendments to the Bill will be considered in the Commons today.
Mr Mercer appeared in the House of Commons chamber yesterday evening in order to reply on behalf of the British government to the adjournment debate.
Boris Johnson official spokesman said earlier yesterday: "Johnny Mercer is a valued minister in the government and we have a good track record on delivering for veterans' issues."
