A UN peacekeeping force has been deployed in the former Spanish colony since 1991 with a mandate to organise a referendum on its independence or integration with Morocco.
Morocco agreed to the vote in a 1988 agreement with the pro-independence Polisario Front that ended 13 years of conflict but has since blocked it being held, saying it will accept only autonomy for the territory.
“No settlement of the Sahara affair is possible outside the framework of the full sovereignty of Morocco over its Sahara and the autonomy initiative, whose seriousness and credibility the international community has recognised,” the king said in a televised address on Monday.
His speech marked 42 years since hundreds of thousands of Moroccan civilians marched across the border to lay claim to the mineral-rich territory.
The “Green March” triggered war with the Algerian-backed Polisario Front which had been campaigning for independence for the territory since 1973.
The UN Security Council adopted a resolution in April that called for a new push for talks between Morocco and the Polisario.
The new UN envoy, former German president Horst Kohler, held talks with both sides last month.
The king said Morocco was committed to contributing to the “new momentum” desired by the United Nations and to cooperating with the new envoy.
But he said it would categorically reject “any overreach, any attempt to undermine the legitimate rights of Morocco”.
The king said Morocco would press ahead with its own plans for the development of the Western Sahara, regardless of the progress of the new peace push.
“We are not going to sit idly by waiting for the solution to be found,” he said.
“We will continue to stimulate the development of our southern provinces and provide their people with the conditions for a free and dignified life.”
Tens of thousands of Sahrawi refugees have lived for decades in desert camps run by the Polisario in neighbouring Algeria.
Spread over 266,000 square kilometres (103,000 square miles) where the desert meets the Atlantic Ocean, the Western Sahara is the last territory on the African continent whose post-colonial status has yet to resolved.
Morocco controls all of the territory’s main towns. The Polisario controls parts of the desert interior.
The Sahrawi Arab Democratic Republic declared by the Polisario is a member of the African Union and recognised by many African governments.
Morocco’s claim to the territory is supported by the Arab League.
The conflict has poisoned relations between Morocco and Algeria for decades. The land border between the North African neighbours has been closed since 1994.
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