Travellers living on Britain's largest illegal site face eviction on Monday, as one resident pleaded with David Cameron to intervene on their behalf.

Bailiffs employed by Basildon Council are due to begin the clearance of 51 unauthorised plots at Dale Farm following a decade long planning dispute.

It is estimated up to 400 people live on the former scrapyard although this number fluctuates as residents travel on a seasonal basis.

Around half of the travellers are believed to have already left the site in Essex, but many have pledged to stay and fight the eviction.

One of the residents, Kathleen McCarthy, issued a last ditch plea to the prime minister to stop the eviction in the interests of keeping families together.

"Now that he is involved in this, my message goes out to him, I beg him and plead to stop this tomorrow," she said.

"We have very sick children and sick people in there," she told Sky News. "He's the man who said he wanted families to stay together."

She added: "He's a family man. I beg him, stop this tomorrow"

Speaking in the House of Commons during prime minister's questions Cameron told John Baron, the local MP, that he supported the eviction plan.

"What I would say is it's a basic issue of fairness. Everyone in this country has to obey the law, including the law about planning permission and about building on green belt land," he said.

"And where this has been done without permission, it is an illegal development and so those people should move away."

In March he said there was a "sense of unfairness" among many people "that one law applies to everybody else and, on too many occasions, another law applies to travellers".

On Sunday Tony Ball, the leader of the council, urged the residents not to resist the eviction.

"I made a final plea to the residents of Dale Farm on Thursday to leave the site peacefully, and whilst some have done this, it is clear than many have not," he said.

"We have always said that the Council and its contractors will carry out what is a difficult operation, in a safe and lawful way. We intend to keep our side of the bargain."