Writing for the Guardian, Abbott and Leigh - the mother and father of the house - said there had been insufficient scrutiny of the bill and urged parliament to instead focus on better health and care services.
Four influential new Labour MPs said they had also decided to oppose the bill amid concerns about the process and the pressure it has put on new parliamentarians.
A vote on legalising assisted dying is to be held on Friday 29 November. It is a free vote, meaning MPs can support or oppose it. In 2015, an assisted dying bill was rejected by 330 votes to 118, but since then a number of countries have legalised the practice and polls show widespread public support.
About 100 Labour MPs are still believed to be undecided. However, the bill's backers remain confident they can be won over.
Keir Starmer and a majority of the cabinet are expected to support the bill, though there have been highprofile interventions opposing it, including from the health secretary, Wes Streeting.
Questions have been raised about the drafting of the legislation - which is a private member's bill from the Labour MP Kim Leadbeater - and whether it is sufficiently watertight.
The Guardian has learned it was drafted by Dame Elizabeth Gardiner, who retired this year after almost a decade as first parliamentary counsel, the government's most senior and experienced legislative drafter.
This story is from the November 21, 2024 edition of The Guardian.
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This story is from the November 21, 2024 edition of The Guardian.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
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