The well-heeled residents of Sandbanks have brought in lawyers to fight plans to replace a hotel at the gateway to the millionaire's resort with a 'soulless' block of flats.

The unprecedented opposition to the £250million project that will see the demolition of the historic Haven Hotel includes over 3,000 letters of objection.

The National Trust has also backed the millionaire locals by slamming the development that will adversely affect the character of the entrance to Poole Harbour in Dorset.

The three-storey hotel was one of the first properties built on the sandy peninsula in 1880 at a time when there were no roads there.

In the late 1890s Italian engineer Guglielmo Marconi used the hotel lounge to conduct his pioneering work on wireless transmission to effectively establish the radio.

Developers have lodged one planning application to bulldoze it and build a six-storey block of 119 luxury apartments that will fund the redevelopment of another two hotels on Sandbanks that are owned by the same company.

Some 250 residents who live on or around the exclusive peninsula, where properties change hands for up to £10m, have mobilised to form the Protect Sandbanks action group.

The group, who include a retired solicitor, architect, town planner and film maker, have brought in a planning barrister to fight the plans and say they are prepared to go to court if necessary.

David Morley, the chairman of Protect Sandbanks, said: "Sydney Harbour has the iconic Opera House, Poole Harbour gets a block of flats.

"The first sight for millions of visitors would be this out of scale, soulless tower block on the beautiful face of Poole Harbour.

"Yes there are some very wealthy people on Sandbanks but there are some quite ordinary people who believe in keeping Sandbanks a beautifully unique place for everybody, not just those who live here.

"It would be completely wrong to say we are just a bunch of rich nimbys.

"We have consulted a planning barrister and as a result have written a letter to the local planning authority to say this application in unlawful.

"You can't buy planning permission. It is not right to have what would otherwise be an unacceptable development in one area just move to another.

"We think they should be separate applications dealt with on their own merits.

"The Haven Hotel sits at the entrance to the harbour. It is free for anybody to go there and enjoy a meal or a drink and take in the view.

"If it was turned into a block of flats that will be closed off to the public. To take it away would be to rip the heart out of the place.

"This site deserves an exemplary piece of architecture befitting its prominent location.

"The proposed blocks of flats are anything but - they are characterless, monolithic and out of scale. They do not fit the character of the area.

"This is a vastly out of scale development for such a sensitive and uniquely important site.

"Nothing on Sandbanks is above five storeys or with this scale or dominance so it sets a dangerous precedent for the future of the peninsula."

Poole is home to the second largest natural harbour in the world behind Sydney and it is also an Area of Outstanding Natural Beauty.

Objections have been lodged by the RSPB over the impact the new buildings will have on bird migration and the Environment Agency due to an inadequate flood risk assessment for the hotel site.

In its letter of objection the National Trust said: "We have significant concerns in relation to the proposed redevelopment of the Haven Hotel site and the height and scale of the proposed residential blocks.

"This includes their impacts on the character and appearance of Sandbanks and the views and setting of the Dorset Area of Natural Beauty."

If approved, as well as the Haven becoming flats, the Sandbanks Hotel would be redeveloped as a new five star 185-bedroom hotel and the Harbour Heights would become a 38-apartment hotel and spa.

The plans have been submitted on behalf of the owner of the three hotels, FJB Hotels, who revised their previous plans for a ten-storey block after sparking outrage.

A 21-day public consultation period is due to take place shortly on the revised plans and the application could go before the planning committee before the end of the year.

Sandbanks famous residents include former football managers Harry Redknapp and Graeme Souness and computer magnate Sir Peter Ogden.