THE cost of replacing the crumbling Comet paddle steamer has been put as high as £750,000, the Telegraph can reveal.

Two shipyards approached in the wake of a marine architect inspection of the derelict vessel have provided individual estimates totalling hundreds of thousands of pounds.

The news comes after a campaigning councillor warned that the outlay would be 'astronomical'.

A report on her condition compiled for the council has declared that repairing the iconic landmark would be 'pointless', given the state it is in.

Councillors are now set to discuss what should happen next.

Comet — an exact replica of Henry Bell's 1812 original which represents so much of Inverclyde's maritime heritage — has been left to rot through a decade-long period of neglect.

A refurbishment costing £180,000 was carried out at Ferguson's shipyard in 2010 but a plan to protect her from the elements with a £165,000 canopy was scrapped.

Now the council is facing up to a rebuild bill of between £250,000 and £750,000 — with the upper figure meaning that nearly £1 million would have been spent since the repair work ten years ago.

The council yesterday declined to name the two shipyards involved in the cost estimates, citing commercial confidentiality.

A spokesman for the local authority said: "They have not been part of any formal tender process and releasing the company details at this stage could be seen to favour or prohibit companies from being involved in any future tendering process.

"They have provided information to the naval architect commissioned by the council and give an outline of the potential costs.

"The costs range between £250,000 and £750,000."

In a report to go before the environment and regeneration committee, director Scott Allan proposes that council officers work with the Port Glasgow Regeneration Forum to 'explore cost options' and report back early next year.

The council spokesman said: "These costs though have not been part of any formal tender process and should not be considered final or agreed.

"They are also not part of any detailed analysis or business plan which, if the report is agreed at the environment and regeneration committee, is work that could be carried out by a working group of the regeneration forum."

A financial package of £50,000 was earmarked by the council 18 months ago for the Comet but the only money spent out of that fund has been £5,000 on the naval architect report.

The council previously blocked the release of the Comet's condition report following a freedom of information request by the Telegraph, stating that it would not be sufficiently in the public interest to do so.