MPs will vote on Labour MP Kim Leadbeater’s Assisted Dying Bill on November 29.
If passed by parliament, the legislation would make it legal to help a terminally ill person with less than six months to live end their life.
Since it is a matter of conscience, MPs will be free to vote how they like rather than being whipped by party managers.
The last time the Commons voted on the issue was in 2015, when parliament comprehensively rejected the proposed law by 329 to 117.
However, given the fact that the make up of the Commons has changed so much since then, the result on November 29 is difficult to predict.
It is unclear whether Keir Starmer - who voted in favour of assisted dying nine years ago - plans to do so again next month.
But there is no doubt that his cabinet are evenly split on the issue.
Here’s what we know so far about the voting intentions of senior ministers and other MPs.
The first cabinet minister to confirm they will vote for the bill was energy and net zero secretary Ed Miliband.
He said: “I will be voting for the assisted dying bill.
“These are very complex and difficult issues and there are very respectable views on both sides.
“For my part, I know there are people who are in the late stages of terminal illnesses, and I think the current situation is rather cruel actually.
“I think people having control over their own life and their own death is something that is the right thing to do.
“Obviously there have to be proper safeguards and I understand the concerns of some people on these issues, but my personal view will to be vote in favour of this Bill.”
Culture secretary Lisa Nandy also plans to vote for the bill, telling BBC Breakfast: “I’ve just seen too many examples of people who have no choices and no dignity at the end of their lives.
“And I think the current system is unsustainable.”
Northern Ireland secretary Hilary Benn has also confirmed that he will vote in favour of the bill, saying: “I remain of the view that those who are facing the prospect of their own imminent death as a result of a terminal illness should be able to determine the timing and the manner of it.”
In what could turn out to be a significant intervention, government chief whip Alan Campbell - the man whose job ordinarily is to tell Labour MPs how to vote - also supports the bill, having voted against it in 2015.
He said: “I plan to be present and to vote in favour of the bill at second reading to allow it to proceed to the committee stage to allow detailed scrutiny.”
Work and pensions secretary Liz Kendall is also backing the bill, saying: “I’ve always believed in giving people as much choice and control as possible, and with all the right safeguards which this bill has, I believe it’s a really important step forward on such a difficult issue, giving people that choice and control.”
Home secretary Yvette Cooper became the latest cabinet minister to say they will vote for the bill.
She told the BBC: “I last voted on this over 20 years ago and my view then was to support the principle of change in this area. It continues to be my view.
“There has to be a detailed discussion on legislation in practice and on the details and the kinds of safeguards that need to be in place. I continue to support the principle [and] will follow the debate on the detail.”
Justice secretary Shabana Mahmood - who as Lord Chancellor would have a key role in implementing the law were it to pass - has said she will be voting against it.
She told The Times: “As a Muslim, I have an unshakeable belief in the sanctity and value of human life.”
And earlier this year she said: “I know some MPs who support this issue think, ‘For God’s sake, we’re not a nation of granny killers, what’s wrong with you’… [But] once you cross that line, you’ve crossed it forever.
“If it becomes the norm that at a certain age or with certain diseases, you are now a bit of a burden… that’s a really dangerous position.”
Wes Streeting, the health secretary, also revealed that he has changed his position on the issue, having voted in favour of it in 2015.
He said: “The challenge is, I do not think palliative care, end-of-life care, in this country is good enough to give people a real choice.
“I worry about coercion and the risk that the right to die feels like a duty to die on the part of, particularly, older people.”
In a further intervention, Streeting said the cost of implementing the legislation if it is passed would also lead to cuts elsewhere in the NHS budget.
Business secretary Jonathan Reynolds is another cabinet member who is opposed to the bill, saying he worries about “how we would protect vulnerable people” if it becomes law.
Bridget Phillipson, the education secretary, said she had not changed her mind since 2015, when she also voted against assisted dying.
According to the Mail on Sunday, Angela Rayner is also planning to vote against the bill, although she has yet to confirm that.
Defeated Tory leadership candidate Robert Jenrick, who voted in favour of assisted dying in 2015, told the party’s annual conference that he would now vote against it.
Meanwhile James Cleverly, who was voted out of the race to succeed Rishi Sunak in the final MPs’ ballot, has also confirmed that he will vote against the bill, just as he did in 2015.
