Morocco has issued arms to civilians on its border with Algeria in order to enable them to face up to what it calls "the agression of the Algerian bullies," according to Foreign Minister Mohammed Boucetta.

The Boucetta statement, made public here today, came amid reports of heavy weekend fighting between Moroccan troops and Algerian-backed Polisario Front guerrillas who are battling to set up an independent Saharan Arab republic in the Western Sahara.

The phosphate-rich Western Sahara, a former Spanish colony, is also believed by some experts to contain the world's largest reserves of uranium.

After reaching a tripartite agreement with Morocco and Mauritania providing for annexation of the Western Sahara by those two countries, Spain withdrew from the territory in 1976. Spain ignored protests from the Polisario Front, which claims to represent the majority of the area's 80,000 inhabitants, and from Algeria, which favored creation of an independent state in the former Spanish colony.

Mauritania signed a peace treat in Algiers last week with the Polisario Front guerrillas under which it renounced all claims to Western Sahara and agreed to withdraw from the disputed territory.

Morocco, estimated to have about 25,000 troops in the Western Sahara fighting Polisario guerrillas, announced last week that, in view of the Mauritania-Polisario agreement, it was pulling out of Mauritania the 6,000 troops it had stationed there to help the Nouakchott government fight against the Polisario.

Morocco since has claimed for itself the former Mauritanian-held sector of the Sahara, known as Tiris el-Gharbia, and has raised the Moroccan flag over the area's capital, Dakhla, last weekend.

Today's statement from the Moroccan foreign minister added that the 6,000 troops scheduled to be withdrawn from Mauritania this week would be concentrated in the former Mauritanian sector of Western Sahara.

In Nouakchott, the Mauritanian government today demanded the immediate withdrawal of Moroccan troops from Mauritanian territory in Western Sahara, adding that the Moroccan move had made it impossible for Mauritania to carry out its "obligations" as provisional administrator of the region under the terms of Aug. 5 agreement under the Polisario.

The Mauritanian government also announced that it will pull its remaining troops out of Western Sahara on Aug. 15 and denounced Morocco's military takeover of Dakhla as an aggression.

Within hours of Morocco's assumption of control of Dakhla, nomadic tribal chiefs and their people were summoned to the desert capital to acknowledge allegiance to King Hassan.

More than a dozen luxurious tents have risen overnight just beneath the walled, royal palace east of Dakhla, ready for the king to receive the tribes' homage. A semicircle of low camel-hide tents have also appeared nearby.

A palace source in Dakhla said that "a vast gathering" was expected at the flag-decked encampment, where the "solemn ceremony" might be marked by an important statement from King Hassan.

In Algiers, a Polisario spokesman said today that 400 Moroccan soldiers were killed and 300 wounded in a clash with Polisario Front guerrillas on Saturday in the heart of Western Sahara. CAPTION: Map, no caption, By Dave Cook - The Washington Post