More than 35 per cent of ambulance handovers to the emergency department at Queen's Hospital took longer than an hour in July, figures show.
London Ambulance Service figures for handover breaches have been published as part of a report to the board of Barking, Havering and Redbridge University Hospitals NHS Trust (BHRUT).
The NHS Standard Contract 2021-22 says all handovers between an ambulance and A&E departments must take place than 15 minutes, with none waiting more than half an hour.
But the LAS data shows that the percentage of 30 and 60-minute breaches at Queen's are the highest they have been in the last 18 months.
The 30-minute handover was breached at the Romford hospital in around 80 per cent of cases in July, with King George Hospital in Goodmayes marginally under the same figure.
Queen's was at 36pc for 60-minute breaches in July, with King George at around 20pc.
The figures were less than 5pc for 60-minute breaches at both hospitals in the early months of 2021.
Matthew Trainer, BHRUT chief executive, said: “Our hospitals are among the busiest in London for the number of ambulances, with Queen’s Hospital often seeing close to 100 a day.
"Too many patients are waiting too long, however, all patients are assessed by a senior clinician on arrival and are not left waiting outside in ambulances.
“We’re working hard to cut the queues in our emergency departments (ED) which lead to these delays, including a new initiative to move elderly patients out of ED much quicker.”
An ambulance receiving centre opened at Queen's in November last year to reduce the time taken for paramedics to hand patients over to ED staff.
The trust, which runs Queen's and King George, did not answer a question from this paper about whether the ARC had been as effective as expected.
In its report, BHRUT said it is planning to review its "frailty pathways" to ensure the frailty receiving units are being "fully utilised".
These units divert over-75s not in need of emergency treatment away from EDs for specialist care.
The trust said it is also planning to open a rapid assessment and focused treatment area at King George "to support ambulance offload".
London Ambulance Service declined to comment.
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