Thousands of graves, some containing the remains of French �migr�s fleeing the French Revolution, are to be dug up to build a new high-speed rail link.

The cemetery near St Pancras station in north London is to be removed to make way for the new terminal for the Channel Tunnel rail link.

Archaeologists, who had hoped to have another two months to identify the graves and try to contact living relatives, have been told their time is up.

The construction consortium building the line said archaeologists always knew there was only a limited opportunity for investigation.

I don't think it is showing respect in the treatment of the dead people in the cemetery

Catherine Cavanagh, English Heritage

The Channel Tunnel Rail Link Company (CTRL) has been able to avoid the normal special permission required when building work disturbs a cemetery.

It operates under a 1996 Act of Parliament, giving it permission to remove graves as long as the work is done with respect and dignity for the dead.

The company said it does not know how many graves will be destroyed and did not reveal how the graves will removed.

A spokesman said: "We have all the relevant permissions required to carry out this process and are currently working with a competent specialist contractor to find the most appropriate methods."

English Heritage, the curator for the site, says the company will send in bulldozers to tip the graves in one mass pile.

The link will bring Eurostar trains to St Pancras

The remains will then be taken away and re-interred at another cemetery in north London.

Catherine Cavanagh from English Heritage said: "It will become like one mass grave.

"I don't think it is showing respect in the treatment of the dead people in the cemetery.

"As well as the ethical aspect, there is a fantastic amount of information that will be lost."

Archaeologists had hoped to gather important evidence about life in London during the industrial revolution from the cemetary, which was first used in 1792.

English Heritage said there were around 4,000 graves.