The town hall has been accused of selling off its family silver after announcing plans to flog a historic piece of land in Hampstead to swell its coffers.

The small plot of land, in front of Burgh House, provided a quiet spot for the contemplation of residents who lived there from the early 1700s.

But the green could soon be paved over as Camden Council begins to plunder its high-value property and land portfolio to fund school and housing projects across the borough.

Trustees at what is now a Grade-I listed museum called an emergency meeting last night to plan a challenge.

Kate Streeter, general manager at the museum in New End Square, said: “The land is as important to maintain as the building itself and we would obviously strongly oppose any plans to develop that land.”

The land was once part of the 18th century house’s grounds and in 1911 got a makeover by Gertrude Jekyll – one of the greatest gardeners of her time.

In 1944 the council bought the freehold to Burgh House on the condition “that any scheme for the development of the site shall provide for the preservation of Burgh House”.

Ms Streeter claims this would prove to be a stumbling block for any developer. “It would be extremely unlikely that planning permission would be granted so I am not having a huge panic,” she said.

The council has not yet decided to sell the site and is consulting residents. The sale would go towards �2million worth of investment needed in Hampstead over the next five years.

A communal garden in nearby Wells House is also under threat and residents there are also mounting a campaign.

John Rice, a leaseholder, said: “The council calls it a communal landscaped area, but we refer to it as our garden.

“People do use it particularly in the summer, with families out picnicking on the grass and children playing.”

Cllr Valerie Leach, cabinet member for regeneration and growth, said: “These are sites the council might decide are surplus to our requirement and we are initially doing a poll on what possibility there might be of development, or if there is very strong community objection and we encourage them to respond.”