Image caption Hospitals are expected to see patients within 18 weeks in England

Patients are being left stranded on trolleys for hours and forced to have treatment in corridors due in part to the loss of hospital beds, nurses say.

The Royal College of Nursing says feedback from more than 1,200 staff paints a "worrying picture", with patients regularly being in ambulances or held in a queue.

The union warned the NHS risked going backwards unless ministers got a grip.

The government said there were enough beds for this not to be happening.

Of the 1,246 nurses and healthcare assistants who replied to an RCN request for feedback, a fifth said providing care in corridors had become a daily occurrence.

Half said they had encountered patients facing long waits on trolleys - with some aware of people being left for 24 hours without a bed.

'Huge stress'

The RCN said that was putting patients at risk by potentially leaving them without access to essential equipment such as oxygen supplies and heart monitoring equipment as well as compromising their privacy and dignity.

Other problems highlighted included ambulances being forced to queue outside A&E units and patients being put in unsuitable wards.

The RCN said the crisis was being caused by a combination of staff shortages, the long-standing drive to reduce the number of beds in hospitals and the rise in A&E admissions.

The union said as a first step the government should call a halt to the reduction in beds. Over the last 10 years, the number of acute and general beds available has fallen by a fifth to just over 100,000.

This has been partly done because of advances in medicine which means patients need to spend less time recovering in hospital and can get a wider range of treatments in the community.

RCN general secretary Peter Carter said frontline staff were being placed under "huge stress", adding the NHS was at risk of going "backwards".

"Treating patients on corridors and areas not designed for care is a high-risk strategy, which can have a serious impact on patient care.

"Patients need to be able to interact with staff, to be able to reach call bells and to know they are visible."

Mike Farrar, chief executive of the NHS Confederation, which represents hospitals, said the problems identified should not be happening.

But he added hospitals were facing a struggle because of "growing financial pressure and significant structural upheaval".

Health minister Simon Burns said: "There is no excuse for patients to be left waiting on trolleys.

"The NHS has beds free and available, and hospitals should be supporting their nurses to ensure that patients are admitted to them quickly. We will not hesitate to take action where we find hospitals failing to do so."