Stone Firms Ltd wants to extract stone from an untouched reserve on Portland
A quarrying company has said it will be forced to start extracting stone from a protected area of the Dorset coast this month, despite local opposition.
Stone Firms Ltd owns the rights to quarry the sought-after Portland stone, and has said it is running out in existing quarries.
It wants to extract stone from an untouched reserve, which consists of 140,000 cubic metres, a 30-year supply.
Some 2,000 people have signed a Downing Street petition against the work.
Tim Clotworthy, of Stone Firms Ltd, said: "It's not sabre rattling, it's what we've got left.
"We've got nowhere else to go.
"We employ 80 people, we've invested million of pounds in new equipment so we are here for the long-term. We will be quarrying."
Michele Ireland says new quarrying will devastate the landscape
The quarrying rights, which were granted in the 1950s, supersede any protection the area has since been given.
Campaigner Michele Ireland, of Southwell Action Team, has started the Downing Street e-petition against the company's plans.
"It's a unique environment from the point of view of its ecology, archaeology and geology," she said.
"It's visited by thousands of people every year, birdwatchers, walkers and climbers.
"It will be devastating if it were to be covered in a lunar landscape."
Dorset County Council is involved in a legal process to alter the planning permissions on Portland, which would prevent an access road being built to a new quarry.
That could scupper any new quarry, but may also mean a compensation payment to Stone Firms Ltd.