An iconic Suffolk lighthouse is doomed to fall into the sea – and the only way to save it could be to move it, according to a coastal expert.

Stuart Bacon, head of the Suffolk Underwater Studies unit, said whatever action was taken to protect Orfordness Lighthouse would ultimately fail as the sea would seek the weakest point to bring it down.

Campaigners have launched a £10,000 appeal to carry out emergency work to bolster the shore in front of the structure, which it is feared could be lost at any time should certain wind and tide conditions prevail.

Long-term, the lighthouse trust wants to raise around £190,000 for sheet steel piling to secure it for 20 years.

Mr Bacon said: “We have had a prevailing southerly-orientated winds now for some time and millions – possibly billions – of tonnes of shingle have been swept away north from Suffolk’s beaches and not all of that material will come back.

“I think anything done to try to protect the lighthouse will be an absolute waste of time, unless you spend millions of pounds on rock defences right away along the edge of Orfordness, which will not happen and I am sure the National Trust would not want as it would spoil the natural environment.

“If you put steel piling in, the sea would go round it and the lighthouse would become an island and still be lost.

“The best answer would be to move it backwards away from the edge to give it more life – it has been achieved with a lighthouse on the south coast, but I don’t know how much it would cost.”

Luke Potter, general manager for east Suffolk for the National Trust, said: “The crux of the situation at our sites at Orfordness and Dunwich Heath is that you never quite know what’s going to happen from one week to the next – these places have evolved over thousands of years and then there can be quite sudden dramatic changes.”

At Dunwich, the trust had bought 36 acres of adjoining farmland to allow for a roll-back when erosion happens, but Orfordness was more difficult as there was pressure from the Alde and Ore rivers as well as the sea.

He said: “We are working as a collective with the Alde and Ore Partnership as well as the lighthouse trust and others as these issues cannot be dealt with in isolation.”