Travellers living on the UK's largest illegal settlement were warned today they would be evicted in two weeks.
Basildon Council will begin the clearance of Dale Farm, near Basildon in Essex, on September 19 after a decade-long row over unauthorised properties on the former scrapyard.
Although half of the site is legal, more than 80 properties have no planning permission and about 400 people are said to be living there illegally.
Travellers and their supporters have promised to resist eviction without violence but police have begun preparations for major disorder.
In a statement, Basildon Council confirmed that travellers had been issued a letter informing them of the eviction date.
The letter encourages them to make homelessness applications as a matter of urgency.
The council also confirmed that electricity supplies to the site would be cut off from September 19 for "safety reasons". Water supplies will continue.
Travellers who need electricity for specific health and welfare reasons have been encouraged to contact the council by September 12.
The authority is also encouraging travellers to contact their GP if they are on medication and to contact Essex County Council about schooling arrangements.
Council leader Tony Ball said: "We have always made it clear that this was a last resort for us, and it is with reluctance that we have been forced to take direct action to clear the site.
"We have sought a negotiated settlement and exhausted the legal system for almost 10 years. In that time the travellers have refused to budge.
"Dale Farm has been illegally developed on green belt land. By doing this and failing to comply with various enforcement notices over a period of years, the travellers have broken the law. As the local authority we are duty bound to see that the law is upheld.
"This is what I also believe the overwhelming majority of the local people expect us to do."
He said the council was not discriminating against travellers as they were being treated in the same way as any other residents who built on green belt land without permission.
Mr Ball added: "We now have a difficult task which we need to carry out in an orderly and lawful fashion with safety the key priority for both the travellers and those involved in the operation.
"We still hope the residents of Dale Farm will reconsider their position and use the final two weeks notice period to move off the site peacefully.
"I hope that any supporters who have gathered at Dale Farm will confine themselves to peaceful and lawful activities. If they really care anything for the travellers they should encourage and help them to move off peacefully in the coming days as we have already asked."
A spokeswoman representing the travellers and their supporters said that the September 19 date meant a longer time-frame than had been expected.
She added: "We were expecting the eviction to be in that week, but this is later than we had believed.
"For the older residents and those with young children it will give them time to make preparations, but it is not a solution - they still have nowhere to go.
"For the supporters, it will act as a focal point for our peaceful resistance. Hopefully, more people will arrive to lend their support now that we have a date."
The Gypsy Council, which is fighting to hold off the eviction, has launched a petition in 11 languages to "get the world to tell the British Government to listen".
Gypsy Council member Joseph Jones said: "Less than a day after the petition was launched in support of the United Nations' call for the eviction to be delayed, it already has 1,321 names.
"We need this delay in order for us to find out what the acceptable solution is."
The petition, published online, calls on Basildon Council to find a "peaceful and appropriate solution" for the gypsy and traveller residents of Dale Farm.
This should include "identifying culturally appropriate accommodation, with full respect for the human rights of the families involved and further, that Basildon Council takes no action against the residents of Dale Farm until such time as it has fulfilled this request".
The United Nations Committee on the Elimination of Racial Discrimination last week expressed regret at the insistence of authorities to proceed with the eviction.