Speaker John Bercow is being urged to grant an emergency debate this week on the Government’s controversial “rape clause” included in the imminent changes to child tax credits.

Alison Thewliss, an SNP MP, who has been a leading opponent of the plans, has written to Speaker Bercow requesting a three-hour emergency debate on the “chaotic” plans.

She hopes MPs will be able to “shine a very bright light on the horror that is about to unfold for rape victims”.

The reforms were first announced by George Osborne, the former Chancellor, as part of a series of measures to save £12bn in welfare expenditure – a contentious move in the party’s 2015 general election manifesto.

It means that families with more than two children will no longer be able to claim child tax credits on a third and subsequent children.

But the policy, which comes into effect in April, means that women whose third child is born following a sexual assault will be forced to provide evidence of the rape to third party healthcare professionals to be exempt from the new restrictions. The exemption has been dubbed the “rape clause” by its opponents.

Alison Thewliss, an SNP MP, who has been a leading opponent of the plans, has written to Speaker Bercow requesting a three hour emergency debate on the “chaotic” plans.

She claims that recent parliamentary answers suggest that the over 660,000 nurses, doctors, and social workers in the UK have not been given adequate sexual violence awareness training to exercise the exemption.

Last week Ms Lewis accused ministers of using a “medieval” and “underhand parliamentary tactic” to “railroad the rape clause into law” without being scrutinised properly by MPs.

She added on Sunday: “With just days until this policy comes into force, this Government is about to unleash utter chaos and untold distress in the public service. This will be in addition to the trauma that rape victims will need to endure as they recount and relive the brutal sexual violence they experienced.

“As it currently stands, doctors, nurses and social workers are going to be asking survivors of sexual abuse to prove they were raped in order to receive tax credits. They've been given no guidance, no training and no advice as to how this should be done. That is truly frightening.

“By invoking Standing Order 24 today, I am pleading with the Speaker to grant an emergency debate on the floor of the House, so we can shine a very bright light on the horror that is about to unfold for rape victims.

“At every turn, this Government has ducked and dived, they've used every trick in the book to sneak this policy through without debate. In light of the issue around lack of training and guidance on this serious matter, I am hopeful that the Speaker will grant this urgent debate.”

There will be no time limit on when the report must be made and third or subsequent children conceived in controlling and coercive relationships will also be exempt, but not if the woman is still living with a partner who could financially benefit from the abuse.

The Government has insisted the data would be treated as “extremely sensitive” and any documentation sent to claimants will not include reason for the additional payments.