Too many local authorities make strategic heritage and cultural decisions on an ad hoc basis and lack any kind of museum plan, according to a report commissioned by the Association of Independent Museums (AIM).

The report, which looked at the changing relationship between local authorities and independent museums registered as charities, found that the UK's independent museums generate £300m a year - a quarter of the museums total.

Adrian Babbidge, the author of the report, said this shows they are "big players in the sector". But the report found that just 0.016 per cent of local authority expenditure goes to independent museums and galleries.

About 8 per cent of local authority expenditure on museums goes to core fund independents.

Acknowledging that local authorities offer museums in-kind support, Babbidge said: "This is a small amount of money in cash terms.

"Where money is being spent, there should be some rationale over why it is giving money away. It is good management."

Babbidge said good practice in areas such as education and health should be replicated in the heritage sector.

"Each council should have a museum strategy for a clear term of years defining its intended relationship and outcomes," he said.

"Museums need to make their voices heard at a more strategic level and at decision-making forums." He said alliances with heritage bodies could help.

AIM chairman Bill Ferris said: "The relationship between local authorities and independent museums has diminished over some years." He added that long-standing agreements were "drifting away".

But he said it wasn't about relying on council money. "We advocate independence and promote an entrepreneurial approach," he said.

www.aim-museums.co.uk