A split is emerging in the cabinet, with Education Secretary Bridget Phillipson revealing she will join several of her colleagues and vote against the bill to legalise assisted dying.
Ms Phillipson told Sky News she will vote against the proposed legislation at the end of this month, which would give terminally ill people with six months to live the option to end their lives.
She voted against assisted dying in 2015 and said: "I haven't changed my mind.
"I continue to think about this deeply. But my position hasn't changed since 2015."
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MPs will be given a free vote on the bill, so they will not be told how to vote by their party.
The topic has seen a split in the cabinet - however, Prime Minister Sir Keir Starmer has yet to reveal how he will vote on 29 November.
Ms Phillipson joins some other big names who have publicly said they are voting against the bill
These include Deputy PM Angela Rayner, Health Secretary Wes Streeting, Justice Secretary Shabana Mahmood and Business Secretary Jonathan Reynolds.
Border security minister Angela Eagle is also voting against the bill.
Senior cabinet members voting in favour of assisted dying include Energy Secretary Ed Miliband, Science Secretary Peter Kyle, Work and Pensions Secretary Liz Kendall, Culture Secretary Lisa Nandy, Northern Ireland Secretary Hilary Benn, Transport Secretary Louise Haigh and Welsh Secretary Jo Stevens.
The split over the issue is said to be causing friction within government, with Sir Keir rebuking the health secretary for repeatedly saying he is against the bill and for ordering officials to review the costs of implementing any changes in the law.
Read more:
What is in the assisted dying bill?
Why is assisted dying so controversial and where is it already legal?
Sky News' deputy political editor Sam Coates has been told Morgan McSweeney, the PM's chief of staff, is concerned about the politics of the bill passing.
He is understood to be worried the issue will dominate the agenda next year and, while he is not taking a view on the bill, he can see it taking over the national conversation and distracting from core government priorities like the economy and borders.
Details of the bill were published last week and include people wanting to end their life having to self-administer the medicine.
It would only be allowed for terminally ill people who have been given six months to live.
Two independent doctors would have to confirm a patient is eligible for assisted dying and a High Court judge would have to give their approval before it could go ahead.
(c) Sky News 2024: Cabinet split over assisted dying as Education Secretary Bridget Phill