The aim of treating people in A&E within four hours is forcing nurses to move patients out of emergency care and into other areas of hospitals.

This means patients with complex needs can be put in units acting as a "staging post" while beds become available in more suitable wards.

Rabina Tindale, a senior lead A&E nurse and chairwoman of the RCN's emergency care association, said peak times have the "biggest impact" on moving patients around.

"It's when the trust is full to capacity and the beds are not available," she added.

Giving examples of the kinds of patients who are moved, she said: "For a patient admitted after a stroke, because there is no bed in the stroke unit they might be admitted to the medical assessment unit. This might only be for 30 minutes or so."

She went on: "Surgical patients have been admitted to an orthopaedic ward or a gynaecological ward to give them that time for when a bed becomes available.

"Although the nurses can care for them, they do not have that specialist experience."

She said the RCN is now calling for a 3% reduction in the target, so that 95% of patients are treated within four hours instead of the current aim of 98%.

Heather Jarman, a consultant nurse and also member of the committee, said patients with complex needs required flexibility of care, including the possibility of them remaining in A&E for treatment or reassessment.