The region is rich in phosphates and fish

In his address on Wednesday, King Mohammed said Morocco would not give up an inch of the region.

He was speaking during a visit to Western Sahara, his second in four months.

The Polisario also accused Morocco of wanting to plunder Western Sahara's resources, which include phosphorous, fish stocks and, perhaps, offshore oil.

Moroccan takeover

Morocco annexed Western Sahara after former colonial power Spain pulled out in 1976.

Since then, the status of the territory has been in dispute.

Most of it is controlled by Morocco - despite the opposition of the Polisario, which fought a sporadic guerrilla war until a 1991 ceasefire.

UN efforts since then to organise a referendum on the status of Western Sahara have been repeatedly frustrated by disputes over who is eligible to vote.

Tens of thousands of refugees remain in camps in southern Algeria

The king's visit came two weeks after a UN report suggested dividing up Western Sahara as one of four options for settling the conflict.

Morocco has rejected the proposal and accused neighbouring Algeria of backing it in an attempt to carve up the area.

The other possibilities put forward by the UN last month are:

• The Security Council imposing terms for self determination
• Making the territory a semi-autonomous part of Morocco
• Pulling the UN out of Western Sahara.