Police numbers will be cut to the "lowest level on record" if the government continues with a plan to overhaul public service pension schemes, shadow policing minister Louise Haigh warned this morning.

Police chiefs wrote to ministers last month to warn that up to 10,000 officers' jobs could be cut because forces face a funding shortfall of nearly £600 million over two years caused by proposed pension changes.

Forces have been told they may have to find £165 million in 2019-20 and up to £417 million in 2020-21 as a result of the change.

Ms Haigh, speaking in the Commons, said: "Despite what the Prime Minister has repeatedly and shamefully told this House, that the police have known about these changes for years, police chiefs issued a public statement rebuking the Prime Minister and stating the first notification they had came in September 2018.

"So quite apart from the fact the Prime Minister should apologise to this House, the government should apologise to the police for such rank incompetence.

"Is it any wonder now that police chiefs are taking the unprecedented step of taking the government of today to court - without the government giving a firm commitment today that the government will meet the full cost of these pension changes it is inevitable that further officers will be lost next year."

Ms Haigh added: "This government isn't just complacent, they are actively making it harder for the police to keep us safe. It's time for ministers to step back from the brink and apologise for the risk they've taken with our safety and give the police the resources they need to fight crime."

Home Office minister Nick Hurd dismissed the comments, telling MPs that Ms Haigh's performance was "one of the most disgraceful pieces of shroud waving" he'd seen.

He added: "The Treasury has made quite clear there would likely be changes to the discount rate that applies to the public pensions. What has changed is the independent Office for Budget Responsibility projections for the future GDP growth which changes the discount rate that applies.

"That is a change I fully accept and she's heard me say that publicly, that has resulted in an unbudgeted cost for the police of around £165 million next year. That is a serious issue, she's heard me say that publicly."

He added: "We are working extremely hard with police and the Treasury to find a solution to this."

Chief Secretary to the Treasury Liz Truss updated Parliament on September 6 about the changes to public sector employment benefits which in effect increase the cost to employers and decrease the burden on employees.

The Home Office has signalled that the 43 forces in England and Wales will need to budget for the extra costs.

Tory MP Philip Hollobone (Kettering) later warned ministers that police finances were "incredibly stretched".

He said: "Dumping £165 million of pension liabilities is going to be the straw that breaks the camel's back. Can I offer him my 100 per cent support in getting the Treasury to think again?"

Lib Dem Sir Ed Davey (Kingston and Surbiton) added: "Police chiefs say this pension deficit, if it's filled, could cost up to 10,000 police officers, does he agree with them?"

Mr Hurd replied: "No I don't - I think the number is exaggerated which is not unusual for the police, but I do recognise that it is... it's in our budgeted cost and what I have given is an undertaking to work very closely with the Treasury and the Home Secretary to find a solution to both this and the additional resources and capacity needed to meet the very real demand pressures on the police."