Lebanon has asked the United States to provide arms and equipment to rebuild its shattered army so that it can patrol the southern Lebanese border with Israel where there has been heavy fighting in recent weeks, Washington Post Foreign correspondent Stuart Auerbach reported.

The request is under consideration in Washington, diplomatic sources said, and was make informally as a test of U.S. willingness to help.

Syria and Egypt have offered to assist in rebuilding the Lebanese army, but their equipment is Soviet-made and some U.S. diplomats here fear that Lebanese acceptance of it could extend Soviet influence into the country.

"We'll get the Russians around selling spare parts during the day and being KGB agents at night," said one diplomat.

The Lebanese request for U.S. military aid comes as Syria, which supplies the bulk of the Arab peace force that ended 19 months of civil war in Lebanon last November, is urging Lebanon to rebuild its army to bring peace along its southern border - the only place in the country where there is still major fighting.

Israeli-supported right-wing Christians two weeks ago fought Palestinian guerrillas aided by Syria for control of Israel's border with Lebanon. The Palestinians captured villages to prevent completion of a string of Christian-held villages along the 60-mile border.

After meeting with Lebanese President Elias Sarkis Saturday, Syria's chief representative in Lebanon, Col. Mohammed Kholi, said a Lebanese army force must be formed and sent to the south.

The army, however, was split into at least four factions during the civil war and there is no unit that could effectively patrol southern Lebanon.