A leader of the Somali rebellion in Southeastern Ethiopia predicted here today that the entire disputed Ogaden region will be "liberated" by the end of this month and that it will then be joined to Somalia.

"This is our aim,"at it will then be joined to Somalia.

"This is our aim," said Sherif Hussein Mohammed, acting secretary general of the Western Somalia Liberation Front, the organization leading the insurgency inside Ethiopia.

"We hope by the end of August to hold talks with the Somali government order to join the Democratic Republic of Somalia," he said in an interview at the front's headquarters in downtown Mogadishu.

The front leader said that the Ethiopian army has lost control of all but about 15 town in the territory regarded by insurgents and the Somali government as rightfully Somalia's. The region sprads across four south-eastern provinces of Ethiopia.

Sherif said that the three main towns still in Ethiopian hands - Harrar, Dire Dawa and Jigjiga - have all been isolated and that only one of four Ethiopian army camps still remains to be captured in a fourth village, Degahabur, in the central Ogaden region.

he said that heavy fighting is taking place between Harrar and Dire Dawa during the daytime and that front commandos are attacking Ethiopian military positions inside the two cities at night, although no frontal assault has been attempted yet on either town.

The international airport at Dire Dawa, a main base for the Ethiopian air force, has been damaged so that jets transport planes can no longer use it he said. But ether diplomatic sources here said they thought the airport is still open to Ethiopian air force traffic.

Somali government sources here said the main theater of the fighting is now 65 miles east of Harrar around Jigjiga, an important Ethiopian armor base that has reportedly been surrounded by Somali rebel forces.

No independent confirmation of any of the claims made by the front or the Somali government was available here, and Western diplomatic circles seem to be at a total loss as to what precisely is happening in the war zone.

However, outside observers believe the front's claim that the Ethiopian army has been routed from a large part of the disputed 100,000 square miles of southeastern Ethiopia claimed by Somalia.

Sherif said that guerrillas have encircled two Ethiopian provincial capitals in addition to Harrar - Goba in Bale province and Negele in Sidamo province. "No one can go anywhere in these two towns," he said.

The front leader also asserted that soldiers of Ethiopia's newly established 100,000 man "peasant army" had proven "aimless and hopeless" in the Ogaden, where they are unfamiliar with the territory, short of food and not fighting to defend home ground.

He said these peasant militiamen had surrendered without fighting in about 20 villages taken over by the front recently.

"It is not their own land," he said.

The front has taken so many Ethiopian army and militia prisoners, he said that "we don't know what to do with them all."

He estimated that 10,000 regular Ethiopian army troops and 15,000 militaiamen are fighting in the disputed territory. The front, he said, has 30,000 guerrillas and 200,000 paramilitary partisans in the towns and villages of the territory claimed by Somalia and his organization.

Sherif said the front has enough arms, thanks partly to the large quantities of Ethiopian military equipment seized by the rebels. He said the front had captured, among other war supplies, 160 trucks used to transport the peasant militia and seven American M-60 tanks in Kebri Dehar in the central Ogaden region.

He said the soldiers who had defecred from the Ethiopian army to the front are now using the tanks against the Ethiopians. No confirmation of this claim was available.

Sherif said the the front plans to hold an international conference in late this month or early next month to announce its intention of merging what the disputed Ethiopian army equipment is to be displayed and one of the main "liberated" towns possibly Harrar, he said.

Until then, journalists will not be allowed to visit the "liberated territory," Sherif said, because heavy fighting still going on makes the area dangerous.