A "SERIOUS" offer has been made to buy and restore a landmark Chepstow ruin as hundreds of acres of woodland surrounding it go up for sale with a £750,000 price tag.

London-based art dealer Edward Strachan has made a new cash offer for Piercefield House backed up by a pledge of £3 million towards repairs.

Leading conservation charity Save Britain's Heritage (SAVE) says Mr Strachan, who previously had a £1 million offer rejected, has earmarked £500,000 a year until the interiors are fully repaired and restored.

The entrepreneur was among those who joined campaigners for a picnic outside the house to draw attention to its plight.

The house was built for Chepstow banker George Smith between 1785 and 1793 by renowned architect Sir John Soanes and it is an important example of his early work.

It has been empty and disintegrating for 70 years with only four roofless walls and two pavilions still standing.

Campaigners say the sale of 203 acres of woodlands known as the Piercefield Walks "presents an extraordinary opportunity to reunite the house and its historic landscape."

According to the website of agents Knight Frank the woods are currently under offer.

The walks are considered to be the birthplace of modern tourism and visitors to Piercefield in its heyday included Nelson and Lady Hamilton and the poets Wordsworth and Coleridge.

The house has been owned by the billionaire Reuben brothers since they acquired Chepstow Racecourse as part of the purchase of Northern Racing in 2006.

A spokesman for SAVE said: "We appeal to the Reuben brothers, property developers of great wealth and patrons of a generous foundation, to declare their future plans for Piercefield House, to reunite the house with the parkland and to give proper consideration to any offers made on the house including the one made (last) week."

SAVE president Marcus Binney added: "Piercefield really is an important house. It's a fine early work by Soane wrapped around an older Baroque house that might have been by William Tulman, (Sir Christopher) Wren's assistant and there's evidence the house has Tudor or even earlier origins."