Keir Starmer has sacked a Labour MP for voting against the government's plans to exempt UK troops from prosecution for war crimes and torture.
Nadia Whittome, parliament's youngest MP, confirmed in a statement that she had been "stood down" from her role as a parliamentary private secretary after opposing the Overseas Operations Bill.
Two other MPs, Beth Winter and Olivia Blake, also voluntarily stood down from similar roles to vote against the legislation, which Amnesty International says will give war criminals "a free pass".
The MPs joined Jeremy Corbyn and 14 other MPs from the left of the party in opposing the bill, which critics say would effectively decriminalise torture. The Liberal Democrats and SNP also voted against the plan.
The new legislation has been slammed by human rights groups and some senior armed forces figures, including General Sir Nicholas Parker Commander in Chief, Land Forces 2010-2012. He argued that the bill would risk the UK being seen as holding itself to "double standards".
Ministers say the bill will protect soldiers against vexatious claims, by creating a blanket presumption against prosecution after five years.
Labour's frontbench says it disagreed with parts of the bill but whipped its MPs to abstain and says it will try to improve the legislation at the committee stage.
The Conservatives appeared unswayed by the opposition's triangulation, broadcasting on their social media channels that the "same old Labour just refused to back Britain's armed forces in Parliament".
Ms Whittome told ITV News that she "thought the bill was a matter of conscience" and did not expect to be sacked for voting against it, describing the legislation as “anti-veteran, anti-human rights, and would effectively decriminalise torture". The bill passed its second reading by votes 332 to 77.
Diane Abbott, the former shadow home secretary, commended the MPs who were sacked or resigned to vote against the bill, saying they had "voted absolutely in line with Labour values".
Defence Secretary Ben Wallace said: “This Government made a promise to the nation to protect service personnel and veterans from vexatious claims and endless investigations.
“We have not shied away from the challenge and today are one step closer to fulfilling that commitment.”
"Our Armed Forces risk their lives to protect us and it is vital we continue to progress this legislation, providing certainty for the troops who find themselves on the front line in the future.”