Hundreds of people are on a waiting list for specialist weight loss treatment in Leeds.
The Tier 3 Weight Management service, designed for adults with severe and complex obesity, had to be closed to new referrals in July 2023.
It was commissioned to help 250 people annually, but had a caseload of more than 1,000 at the end of December.
About 660 people are waiting for treatment and the NHS said those patients were being guided to other sources of support.
The service is delivered by Leeds Community Healthcare NHS Trust (LCH) and helps people with a body mass index of 40 or higher, or 35 if they have other health problems, the Local Democracy Reporting Service said.
However, a report to the LCH's board meeting said: "The waiting list continues to grow and remains significantly above contracted levels."
New treatments, including injections for weight loss, could be used as part of a reorganisation of the service.
However, the report said the West Yorkshire Integrated Care Board (ICB), which commissions the service, was concerned about the "financial impact to the system of a large-scale roll out".
They said the service was working to deliver a "phased-approach".
The ICB put an extra £192,000 into the Tier 3 service, but the additional money would not be available after April, the report added.
It said a decision on investment for the service, which works with patients over 12-18 months, would be made before the end of March.
"Many areas across the UK do not have access to a specialist service like the offer we have available in Leeds," a spokesperson said.
“As a healthcare system we are working within challenging financial constraints, and therefore identification of further investment has to be balanced against other statutory duties."
They said digital treatments, mental health support, more education and a review of the referral criteria were among planned improvements.