French authorities are ordering hundreds of refugees to vacate a large swathe of a vast camp along the English Channel in Calais.

Those occupying the southern sector of the camp, often referred to as "the jungle" because it is the most densely populated section, have until Tuesday evening to vacate the premises before it is razed by authorities.

The order comes from the state authority for Calais, which adds that police are authorized to remove anyone still on the premises.

Official estimates of the number of people in the targeted area vary widely – from 800 to 4000. This section of the camp is replete with cafes, shops and houses of worship.

Many of the refugees in the camp are fleeing civil war and conflict in Syria, Iraq and Afghanistan, but others, from Africa, are fleeing countries with poor human rights records.

French authorities want them to move to nearby heated containers or welcome centers around the country, and to reconsider their dreams of reaching Britain on the other side of the English Channel.

Celebrities speak out

But that idea is being countered by Hollywood actor Jude Law and nearly 150 other celebrities, who sent an open letter to British Prime Minister David Cameron, calling on him to open Britain's doors, at least to the migrant children who have relatives in Britain.

Law, who organized the letter and visited the camp, described conditions there as "horrific" for unaccompanied children.

"These are innocent, vulnerable children caught up in red tape with the frightening prospect of the demolition of the Jungle hanging over them," he said.

"David Cameron and the British government must urgently work with the French authorities to alleviate this humanitarian crisis."

The celebrities, who also include Gillian Anderson and footballer Gary Lineker, slammed the French government's plan to force people out of the camp, saying some 3,000 people will be made homeless with temperatures hovering around freezing.

"Such an enforced move would uproot again those who have already had to abandon their homes due to war and persecution," read the celebrities' letter.

The charity Help Refugees says there are 440 children living in this section of the camp, 291 of whom are unaccompanied by an adult.

Eight aid organizations working in the camp also sent a protest letter to the French interior minister claiming that the government's proposed plan is "very far from answering the needs of the problems encountered."

Interior Minister Bernard Cazeneuve responded, saying the evacuation would go ahead "progressively."

bik/bw (AP, AFP)