Veterans minister Johnny Mercer has quit the UK government, a Downing Street spokeswoman confirmed.
Described by Downing Street as a "valued minister", Mr Mercer is thought to be unhappy about the government's inability to stop investigations into former personnel during the Troubles in Northern Ireland.
He has been involved in the Overseas Operations (Service Personnel and Veterans) Bill, which is going through its final stages in Parliament.
The legislation was developed after legal claims were made about operations in Iraq and Afghanistan. However, it does not cover incidents in Northern Ireland.
The Prime Minister’s official spokesman said: “I’ve seen there is speculation, and speculation is what it is at the moment."
He continued: “Johnny Mercer is a valued minister in the Government and we have a good track record on delivering for veterans’ issues.”
A statement released shortly after 7pm 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.”
Mr Mercer shared his letter to the Prime Minister on Twitter. It read: “It is with a heavy heart that I am forced to offer you my resignation from your Government.”
He said he had hoped Mr Johnson’s premiership would “signal a step change in veterans affairs in the UK”.
Mr Mercer 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.”