The author John Fowles has joined a campaign against a housing development in Lyme Regis, saying it threatened to turn the seaside idyll into "Surrey by the sea".

Residents fear the proposal would ruin the view from the Dorset town's harbour and its stone breakwater, the Cobb, that was made famous by the film of Fowles's novel, The French Lieutenant's Woman.

He has joined 20 other residents in objecting to an application to turn a hotel into five houses, seven flats and four two-storey homes, which would also mean felling a number of trees.

If approved by West Dorset council, the homes would sit on the highest land in the town, dominating its skyline, say the protesters.

In a letter to the local weekly, Fowles warns that Lyme Regis could fail in its attempt to become a world heritage site. "Lyme Regis is treasured by us who are lucky enough to live here but it is equally loved by visitors from around the world," he wrote. "Let's stop destroying it and turning into another little suburban town.

"These [trees] all give a wonderful skyline looking up from the Cobb and Marine Parade. Why allow these visible trees to be given over to car parking? I am sure West Dorset council is aware this coast is nominated to become a Unesco world heritage site, so to turn Lyme Regis into Surrey-by-the-sea may not help this cause which is so important to Dorset."

Fowles, who has lived in Dorset since 1966 and published his novel in 1969, told an interviewer this year: "I could not wake up and not hear the sounds of the waves."