Fresh guidelines on assisting suicide could open a "new back door" to euthanasia, the Commons heard today.
MPs called for a debate on the issue after Director of Public Prosecutions Keir Starmer said the guidance would place closer scrutiny on the motivation of the suspect.
The stricter, final version of the policy will also place less emphasis on the health of the victim - such as whether they are terminally ill.
It also makes clear that anyone assisting suicide who benefits from the death is unlikely to be prosecuted as long as compassion was the "driving force" behind their actions.
But during questions on future business in the Commons today, MPs demanded time to debate the changes.
Labour's David Winnick (Walsall N) stressed the importance of debating the policy "in view of the controversy about assisted suicide".
And Tory Mark Pritchard (The Wrekin) said it was up to Parliament to set the law and the courts to interpret that.
He said: "There is real concern out in the community that this House is not having a say. People are very concerned that this is a new back door to euthanasia in the UK."
Commons leader Harriet Harman stressed there had been no change in the law and said she would consider giving time for MPs to debate the issue.
She added: "We have got new guidelines under the order of the court that has been brought forward by the Director of Public Prosecutions and I think the position is clear."
Gordon Brown has warned against legalising assisted suicide, saying it would run the risk of putting vulnerable people under pressure to end their lives.
In a newspaper article this week the Prime Minister warned: "The risk of pressures - however subtle - on the frail and the vulnerable, who may for example feel their existence is burdensome to others, cannot ever be entirely excluded."
However 'right-to-die' campaigner Debbie Purdy criticised Gordon Brown, arguing the PM had shown a "lack of respect" to the British people.
She believes changing the law will allow more open discussion, meaning patients will not feel abandoned and lives will actually be saved.