Image caption Currently, 18% of England's forests are publicly owned

The National Trust is promising to "play its part" in protecting England's ancient woodlands if a planned sell-off of publicly-owned forests goes ahead.

Up to 2,500 sq km could enter private hands, but critics say that would damage nature and restrict access.

The National Trust says it is looking at various options, including buying the most sensitive areas, such as the New Forest, itself.

The government said it welcomed ideas from all interested parties.

A consultation has been launched on the future of about 1,500 pieces of land in England - the 18% of English forests owned by the Forestry Commission.

Under the government's proposals, commercially valuable forests, such as Kielder, could be sold to timber companies on long leases, while communities, charities and even local authorities would have the opportunity to buy or lease other areas.

Ministers say ancient woodlands, such as the New Forest and the Forest of Dean, would be kept out of commercial hands and instead be managed by charities, with access rights preserved.

'Special places'

The National Trust, which protects buildings, countryside and coastlines in England, Wales and Northern Ireland, said the plans were "a watershed moment in the history of the nation".

"If the government is determined to pursue the course of action it has outlined and the public wish us to, we are ready to play our part in giving them a secure future," the charity said in a statement.

We're interested to hear ideas from all interested parties Spokesman, Defra

"It is therefore essential and urgent that everyone who cares for these special places now make their voices heard over what should happen to them.

"The secretary of state has given assurances that access, conservation and the amenity value of these forests will be guaranteed in perpetuity, but there is, as yet, no explanation as to how this will be ensured."

The Trust is said to be considering a number of options, including taking over forests itself, but because of the large costs involved, it is hoping to enter into discussions with potential partner organisations.

It is now asking conservationists, charities and ordinary forest users to come forward with their suggestions on how it should proceed.

Responding to the Trust's statement, a spokesman for the Department of Environment, Food and Rural Affairs (Defra) said it was "interested to hear ideas from all interested parties as part of this consultation process".

Environment Secretary Caroline Spelman has said it is "time for the government to step back" for forest management, while ensuring "that public access is maintained and biodiversity protected".

But high-profile opponents, including the Archbishop of Canterbury, Dame Judi Dench and author Bill Bryson, have described the privatisation as "unconscionable".

And the campaign group 38 Degrees says more than 250,000 people have signed its online Save Our Forests petition.

The consultation runs until mid-April. Scotland, Wales and Northern Ireland are not affected by the plans.