Prime Minister Boris Johnson has accepted the resignation of Johnny Mercer as veterans minister, a Downing Street spokeswoman confirmed.
Mr Johnson thanked Mr Mercer for his service as a minister, according to a Downing Street spokeswoman.
In a statement released shortly after 7pm, the spokeswoman said: '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.'
Johnny Mercer, pictured, has resigned this evening from Government in a row over the treatment of veterans accused of crimes in Northern Ireland
The former British Army officer was reported to be unhappy about a lack of progress in dealing with former personnel being investigated for killings during the Troubles in Northern Ireland.
In a Tweet, Mr Mercer said: 'I’m sorry to have been relieved of my responsibilities in Government tonight.'
He 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.
The Telegraph reported that Mr Mercer had become increasingly frustrated about the lack of progress on the Northern Ireland issue.
Lords amendments to the Bill will be considered in the Commons on Wednesday.
Mr Mercer appeared in the House of Commons chamber on Tuesday evening in order to reply on behalf of the Government to the adjournment debate.