A ministerial aide has been sacked from his government role after calling for a ceasefire in Gaza.
Downing Street said Paul Bristow had made comments which "were not consistent with the principles of collective responsibility".
In a letter to the prime minister last week, Mr Bristow said "a permanent ceasefire" would save lives and allow aid to reach those who needed it most.
The government supports "humanitarian pauses" but not a full ceasefire.
During Prime Minister's Questions last week, Rishi Sunak said "specific pauses" would allow more aid into Gaza but he rejected calls to back a ceasefire, stressing that Israel had a right to defend itself.
Mr Bristow, who is the Conservative MP for Peterborough, was a Parliamentary Private Secretary - the lowest rung of the ministerial ladder - to Michelle Donelan, the Secretary of State for Science, Innovation and Technology.
After being sacked by Mr Sunak, he told the BBC: "I completely understand the PM's decision. And it is with regret I leave a job I enjoyed. "But I can now talk openly about an issue so many of my constituents care deeply about.
"I believe I can do this better from the backbenches rather than as part of the government payroll."
A Downing Street spokesman said: "Paul Bristow has been asked to leave his post in government following comments that were not consistent with the principles of collective responsibility."
Collective responsibility is the convention that all members of the government must publicly support government policy, even if they personally disagree with it.
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History behind the story: The Israel-Palestinian conflict
A large number of opposition MPs have backed calls for a ceasefire but very few Conservative MPs have.
Labour leader Sir Keir Starmer is under increasing pressure to support a full ceasefire, with senior figures including London mayor Sadiq Khan, Scottish Labour leader Anas Sarwar and a number of frontbenchers supporting one.
So far, Sir Keir has only backed humanitarian pauses, aligning him with the position of the UK government, as well as the US and EU.
Compared to a formal ceasefire, humanitarian pauses tend to last for short periods of time, sometimes just a few hours.
They are implemented purely with the aim of providing humanitarian support, as opposed to achieving long-term political solutions.
Earlier, Israel's Prime Minister Benjamin Netanyahu told a press conference his country "will not agree to a cessation of hostilities with Hamas".
"Calls for a ceasefire are a call for Israel to surrender to Hamas," Mr Netanyahu said.
In his letter to the prime minister on Thursday, Mr Bristow, wrote: "My constituents and I are deeply grieved by the heart-breaking and devastating humanitarian crisis now unfolding in Gaza.
"Thousands have been killed and more than one million now displaced.
"It is difficult to understand how this makes Israel more secure or indeed makes anything better."
He added that some of his constituents had been directly affected by the conflict.
Posting the letter on Facebook, he wrote that ordinary Palestinians "should not suffer collective punishment for the crimes of Hamas".
Collective punishment is prohibited under international law.
Around 18% of people in Mr Bristow's Peterborough constituency are Muslim, according to the latest census.
It is a marginal seat, which he won from Labour with a majority of 2,580 at the last general election.
Meanwhile, Andy McDonald has been suspended as a Labour MP, after the party said he had made "deeply offensive" comments relating to the Israel-Gaza war.
Israel has been bombing Gaza since the 7 October attacks by Hamas that killed 1,400 people and saw at least 239 people kidnapped as hostages.
The Hamas-run health ministry in Gaza says more than 8,000 people have been killed since Israel's retaliatory bombing began.