Image copyright Jim Phanco Image caption The Inchgreen dry dock is one of largest in the UK

Senior politicians from three parties have backed calls for a new industrial strategy to help "save" former ship repair sites on the Clyde.

A letter to First Minister Nicola Sturgeon says the Inchgreen dry dock in Greenock and Govan Graving Docks have needlessly been allowed to decay.

Campaigners want an action plan to stop marine industry sites being lost to housing or retail development.

The owners of both sites have insisted they have plans for their future.

The STUC along with 23 MPs and MSPs from the SNP, Labour and the Greens have endorsed a joint letter to the first minister from the Campaign to Save Inchgreen Dry Dock and the Clyde Docks Preservation Initiative.

The Inchgreen dock, one of the largest in the UK, is where the QE2 was fitted out in the 1960s after its launch from the John Brown shipyard.

Image copyright PA Image caption The Inchgreen cranes were demolished in July 2017

But it has been largely unused for 16 years and its cranes were demolished last summer.

Campaigner and former shipyard worker Robert Buirds has accused its owner Peel Ports of starving the facility of investment, while at the same time investing heavily in the Peel group's main ship repair interests at Cammell Laird in Merseyside.

He said: "We've had at least two companies that have asked to lease Inchgreen - but the price they were looking for the lease made it completely uneconomical.

"That's two companies who have a vision for Inchgreen - who think they can expand Inchgreen and use it for shipbuilding or marine engineering."

Peel has robustly defended its investment record, saying it has created more than 5,000 jobs in Scotland in recent years.

Cammell Laird, which manages Inchgreen on behalf of Peel, says it is currently bidding for refit contracts for the Navy's new aircraft carriers which could give the Inchgreen dock a new lease of life.

Image caption The Govan Graving docks have been unused for 31 years

The A-listed Govan Graving Docks, derelict for 31 years, are owned by property developer New City Vision, which was recently refused planning permission for 700 flats, shops and office space on the site.

Port Glasgow-based Ferguson Marine, owned by billionaire Jim McColl, is understood to have expressed an interest in using both Inchgreen and the Govan site for shipbuilding or repair.

The letter to Ms Sturgeon warns that cash-strapped local authorities could be tempted to accept short-term offers of investment that fail to provide skilled employment, with industrial land disappearing "never to return".

Robert Buirds added: "I'm not complaining that they're not investing. I don't believe they're investing in the right places that brings the amount of work and skilled jobs that I believe the River Clyde requires."

The campaigners have asked the Scottish government to produce a strategy to promote and co-ordinate investment in marine industry on the Clyde.

The Peel group acquired numerous industrial sites and tracts of waterfront land on the Clyde though its acquisition of Clydeport in 2003.

Elsewhere, it has recently announced plans for a major retail and leisure development near Glasgow's Riverside Museum, and an upgrade to its cruise liner terminal in Greenock.

No-one from New City Vision or Peel was immediately available for comment.

The letter is endorsed by MPs Ronnie Cowan, Paul Sweeney, Mhairi Black, Gavin Newlands, Brendan O'Hara, Carol Monaghan, Patricia Gibson, Alison Thewliss and MSPs Richard Leonard, Patrick Harvie, Gil Paterson, Ross Greer, Jackie Balllie, Stuart McMillan, Claudia Beamish, Neil Biddy, John Finnie, Ruth Maguire, Jonan McAlpine, Emma Harper, Kenneth Gibson, David Stewart and Rhoda Grant.