An intensive care ward for mental health patients will be temporarily shut next month because of "low staffing numbers".
As first reported in the Ipswich Star, the Norfolk & Suffolk NHS Foundation Trust (NSFT) said it was unsafe to use the mixed-sex Lark Ward in Ipswich.
The trust said its general acute wards or psychiatric intensive care wards could be used instead.
Lark Ward will close on 6 April, with no date fixed for reopening.
The NSFT is the NHS's mental health services provider across the two counties and Lark Ward is at its Woodlands Unit which is on the Ipswich Hospital site.
The ward, which treats people with disorders including schizophrenia and personality disorder, is meant to have a staff-patient ratio of 2:1.
'Months not weeks'
In October, the trust temporarily reduced bed numbers from 10 to seven, due to reduced staffing levels.
Pete Devlin, the trust's operations director for Suffolk, said: "Lark Ward is a mixed sex, psychiatric intensive care unit and, as such, it needs a higher staff-to-patient ratio, to ensure we can provide more intensive treatment for the most acutely unwell patients, [and] for short-term admissions.
"Staffing levels will continue to be reviewed and the beds will be reinstated when it is fully safe to do so."
But he added this is likely to take "a few months rather than weeks".
Mark Robinson, an officer with the health workers union Unite, said staff from neighbouring wards had raised concerns about the closure.
He said: "It's an example of the increasing difficulties in recruiting highly-qualified staff, both clinical and non-clinical, in specialist areas in the NHS."
He hoped the NHS pay deal would help with future recruitment.