The prime minister said there was a “clear moral case” for his reforms, which include measures designed to slash £5bn a year from the welfare bill by 2030.
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While many Labour MPs initially indicated they backed the bill in principle, support has ebbed away over recent months amid warnings about the impact the cuts could have on the most vulnerable in society.
Around 119 Labour MPs have now signed a “reasoned amendment” to oppose the government’s proposals – which, if passed, would effectively kill the legislation.
However, speaking to reporters on the plane to the NATO summit in The Hague, the prime minister reiterated the case for the so-called Universal Credit and Personal Independence Payment (PIP) Bill, despite the building opposition from his own side.
“There is a clear moral case, which is the current system doesn’t help those who want to get into work,” he said. “It traps people.”
Welfare system ‘unsustainable’
Sir Keir said around 1,000 people a day were going on to PIP – equivalent to the size of the population of Leicester.
“That is not a system that can be left unreformed, not least because it’s unsustainable, and therefore you won’t have a welfare system for those that need it in the future,” he continued.
“So those that care about a future welfare system have to answer the question – ‘how do you reform what you’ve got to make sure it’s sustainable for the future?'”
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On Tuesday, Downing Street suggested the vote would still go ahead despite the public concerns of some MPs – including influential chairs of parliamentary select committees.
Asked whether the government was confident it could pass the legislation, a Number 10 spokesman told reporters: “We are focused on delivering last week’s bill and engaging, talking to colleagues, as to why this reform is so important.”
Pressed on whether the vote was happening next week, they added: “I would never get ahead of parliamentary business. It’s scheduled for next week. We are committed to reforming welfare.”
Introduced in March, the government’s welfare bill outlines proposals to make it harder for some disabled people to qualify for personal independence payment (PIP) while also cutting another benefit, Universal Credit.
The reasoned amendment, which has now been signed by 119 Labour MPs, calls on the government to delay its flagship proposals pending an assessment of the impact of cuts to PIP.
It also cites concern about the the government’s own figures which show 250,000 people could be pushed into poverty as a result of the changes and the fact the provisions have not been subject to a formal consultation with disabled people.
One Labour MP who had signed the letter told Sky News they were not comfortable with the bill because it penalised those who were already in work.
“If the thrust of the policy is getting people into work, how does cutting support for people in work, work?” they said.
“The thrust of the proposals is right but cutting PIP and Universal Credit isn’t about getting people back into work, it’s about saving money.”