GPs in Hammersmith and Fulham have called on the NHS to release £1 million to "tackle the current health care crisis in the borough".
The Hammersmith and Fulham GP Federation has made the request to Hammersmith and Fulham Clinical Commissioning Group (HF CCG), and says time is running out to spend the money.
The federation says £1.3 million has been available to spend on primary care in the borough since April 2017, but to date only £40,000 has been released.
It says the full amount must be spent by March 31 or it will, in effect, be lost.
Failure to spend the money will see patients in the borough miss out on extra nurses, health care assistants and doctors, it is claimed.
The federation says it is "hugely concerning" that so little of the money has been allocated.
It has worked with GPs to develop a large number of proposals to improve patient care in the borough, including home care for frail elderly people, care navigators to direct patients rapidly to the right place, and new systems to improve communications between GPs and hospitals to ensure access to specialist advice when needed.
Dr David Wingfield, Hammersmith and Fulham GP Federation chairman, said failure to spend the money meant GPs were unable to take the burden off hospitals.
He said: “It is clear that the HF CCG is working far too slowly to invest the available NHS funds before March 2018 and this will prevent patients in the borough from benefiting from this necessary extra investment in their care.
"We will not be able to appoint much-needed extra nurses, health care assistants and doctors as we had hoped.
“This is particularly frustrating at a time when hospitals are struggling to cope and all efforts need to be strengthened to keep patients well-cared for in their own homes.
"We have written to the CCG to ask for the pace of investment in patient care to be accelerated this winter.
“The people in the borough who are most impacted are the old and young, for whom many of the planned initiatives that require the funding are intended for.
"The workforce is also impacted as GP practice staff are becoming increasingly disillusioned with the lack of funding in primary care and seeking roles elsewhere."
He added: "Wards are full of patients who in principal should be at home but practically can't be because of the limited resources in general practice and community care.
"What we have got is hospitals really needing the most support from the doctors and nursing colleagues in the community.
"It's quite remarkable. We have the funding but it's not being released at a rate which is commensurate to the need of the NHS.
"We work very closely with the CCG but our frustration has just boiled over.
Hammersmith & Fulham GP Federation say it is yet to hear back from the HF CCG.
An HF CCG spokesman said: "We have been working closely with our GP practices to invest this money in achieving tangible benefits for our residents.
"Given the significant progress that has been made in this area over the past few months, we would suggest that the position is positive.
"We have approved over £400,000 already on proposals, and are developing plans over the next weeks for up to £600,000 of additional investment.
"It continues to be our shared ambition to use this money to improve care and experience for local residents by going through due process, as we do with all of our commissioning decisions."
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