Backed by U.S. made F-5 fighter bombers, Ethiopia began to airlift regular army reinforcements and the vanguard of its new peasant army to join the 16-year-old war against Eritrean rebels yesterday.

The regular troops were flown in civilian aircraft north to Asmara, capital of Eritrea Province, and to the Ogaden desert region in the southeast, where 4,000 well-armed and well-trained guerillas from the Liberation Front for Western Somalia have virtually pinned down government troops.

Diplomats said advance elements of the peasant army, reported to number 300,000, have already joined troops in the north in preparation for a new drive to crush the insurgents.

Heavily armed troops of the Flame Division, trained by Israeli specialists, were seen boarding an Ethiopian Airlines plane at the civilian airport.

Many carried rocket launchers, mortars and American-made machine guns and rifles.

Diplomatic sources said that in addition to 80 Soviet-made T-54 and T-55 tanks that recently arrived in Ethiopia, the government is expecting a shipment of Mig fighters to bolster its small and mainly American-equipped air force.

Also yesterday, Libya announced that it had signed several economic and technical agreements with Ethiopia.

Ethiopia said it and the new republic of Djibouti had agreed to hold a highlevel meeting to strengthen cooperation.