Medway Maritime Hospital has been warned its A&E department could be downgraded or even closed if urgent improvements are not made.

Health watchdog Care Quality Commission (CQC) made an unannounced inspection at the department at the end of July and raised ongoing concerns about the standard of care.

As a result, the failing NHS hospital was issued with a notice from the CQC, informing the trust of its intention to use, if necessary, Section 31 of the Health and Social Care Act.

If immediate improvements are not made, the CQC could use section 31 to limit or close A&E services.

A hospital spokesman said "urgent work" was taking place in the department.

She added: "We recognise the CQC continue to have concerns around the standard of care, specifically around the emergency care pathway.

"Urgent work is now taking place with the CQC and our local healthcare partners to implement immediate actions and to ensure robust plans are in place.

"We will continue to take all necessary measures to ensure patients receive the care they need."

Prof Sir Mike Richards, CQC's Chief Inspector of Hospitals, said: "We have previously reported our concerns with the quality of the service provided by the Accident and Emergency Department (A&E) at Medway Maritime Hospital, and carried out a further unannounced inspection.

"The A&E department is being monitored closely. We will report back on our findings and any action we may take in due course."

"We are, of course, very concerned that the most recent CQC inspection shows there are still issues with the standard of care at the A&E department..." - Dr Pete Green

Last Monday, ambulances were diverted from Medway A&E as the department struggled to cope. Patients arriving by ambulance were sent to Darent Valley Hospital during a two-hour period. A spokesman for the trust said diverting ambulances was "not uncommon" in the NHS.

Dr Pete Green, chairman of Medway Clinical Commissioning Group (CCG), which buys health services for the Towns, said the move was carried out to "ensure safe services could be maintained".

The following day, a GP training event was cancelled so doctors could keep practices open to relieve some of the pressure.

Dr Green added: "The CCG, and GPs in Medway are working with Medway NHS Foundation Trust and other providers to improve services and that includes helping to avert pressure from A&E.

"We are, of course, very concerned that the most recent CQC inspection shows there are still issues with the standard of care at the A&E department."

Patients are still waiting too long to be seen at Medway's A&E, the report found.

The longest wait in June was 24 hours 50 minutes – a "continued deterioration on the April and May performance".

The trust failed to meet the national A&E target of seeing 95% of patients within four hours. Medway only treated 81.06% of admissions in this time. Almost 6% left A&E without being seen.

Last month, the hospital was told it must remain in special measures after being rated inadequate.

Inspectors said insufficient progress had been made in A&E since a damning report in February.

Patients were "stacked" in corridors and some were left on trolleys overnight in "inappropriate areas".

Out-of-date and damaged equipment was found, fire exits were blocked and the department was not "consistently clean".