An NHS Trust whose chairman resigned in protest at Government funding has been put into special measures.
The former head of the civil service, Lord Kerslake, quit as chairman of King's College Hospital NHS Foundation Trust in south London on Sunday, warning that the health service could not continue "staggering along" under the current funding levels.
On Monday, NHS Improvement put the trust into special measures, citing "serious concerns" about its growing deficit, which had deteriorated at a greater scale and pace than any other hospital trust.
Ian Smith has been appointed by the body as interim chairman.
The quango said King's board had earlier this year agreed a budget deficit with it of £38 million for 2017/18, but last week forecast it would hit £92 million - an increase of £54 million.
NHS Improvement chief executive Ian Dalton said: "The financial situation at King's has deteriorated very seriously over recent months and we have now placed the trust in special measures to maximise the amount of scrutiny and support that it receives.
"We understand that the wider NHS faces financial and operational challenges, and other trusts and foundation trusts have large deficits.
"However, none has shown the sheer scale and pace of the deterioration at King's.
"It is not acceptable for individual organisations to run up such significant deficits when the majority of the sector is working extremely hard to hit their financial plans, and in many cases have made real progress."
A financial improvement director will now be appointed to oversee King's, which will also be required to draw up and deliver a plan to improve its finances.
Lord Kerslake told BBC Radio 4's Today programme there was "not enough understanding of the scale of the challenge that both King's and the NHS is currently facing".
"We face some here and now issues," said the crossbench peer.
"I am deeply concerned about the position generally, actually, in London where most of the hospitals are struggling.
"But there is also a big issue about social care as well which got no additional funding in the Budget.
"And I think, deep down, what we need is a proper review, a cross-party review, I don't mind what it's called, that looks at what kind of NHS do we want, how much is it going to cost and then how are we going to pay for it.
"Unless we do that we are just going to carry on staggering along, kicking the can down the road and not really addressing the fundamental issue."
Lord Kerslake, who has carried out some work for Labour, insisted that his decision to speak out was motivated by a "deep passion for the NHS" and was "nothing to do with party politics".
Shadow health secretary Jonathan Ashworth said: "This is embarrassing for the Government and is evidence from a heavily respected figure on the frontline that the Budget utterly failed to deliver for the NHS and that seven years of underfunding is impacting on patients in unacceptable ways."
A Department of Health spokeswoman said: "We know that King's NHS Foundation Trust faces huge financial challenges and we will support them to tackle these issues and continue to deliver high quality care for patients under a new chairman.
"We would like to thank Lord Kerslake for his service."
Niall Dickson, chief executive of the NHS Confederation, described Lord Kerslake's decision as significant "not least because he has been at the heart of government".
He said that the Government has "enormously difficult decisions to make" and added: "But what is unarguable is that demand is growing beyond our capacity to meet it - and ironically the current constraints are slowing down our capacity to reform the way care is delivered.
"As a society we have to decide whether or not we are prepared to take a hard look at what will be needed, embrace reform and provide the resources needed to deliver it."
Copyright (c) Press Association Ltd. 2017, All Rights Reserved. Picture (c) Andy Hepburn / PA Wire.