Artillery fire from a rightwing Christian Militia stronghold in southern Lebanon yesterday halted the Lebanese army's long-awaited move into that part of the country bordering Israel.

The shelling, in which one Lebanese soldier was wounded, showed the Israeli-backed militiamen's determination to resist any entry by the newly rebuilt army, which they view as pro-Syrian and soft on Palestinian guerillas.

Diplomats see the deployment of the army in the south as a crucial test of the Lebanese government's ability to impose its authority over the numerous armed factions in the country. The move, which has been promised repeatedly for at least a year, is also vital for U.N. peacekeeping forces to be able to fulfill their mandate.

The 500-man Lebanese battalion, supported by light tanks and field artillery, was due to cover about 70 miles from its barracks in estern Lebanon to the Moslem town of Tibnin, about eight miles north of the Israeli border in an area controlled by the U.N. force.

But the convey of troop-carrying trucks and armored vehicles as well as buses and cars filled with reporters, was stopped at the village of Kaukaba as it approached the Christian rightist stronghold of Marjayoun. Phosphorous marker shells landed about 200 yards away in a clear warning not to advance. Maj. Saad Haddad, a renegade army officer who controls the Christian militias in his area, then gave the battalion an ultimatum to withdraw, according to U.N. sources.

When it still had not a couple of hours later, he unleashed an artillery barrage which wounded one soldier, sources in radio contact with the area said.

Two Lebanese Air Force Hawker Hunter fighters also came under fire when they flew reconnassiance over the rightist stronghold. They were not hit.

Neither the planes nor the army battalion returned the fire, military sources said. Col. Adib Saad, the battalion commander, said the troops would stay overnight in Kaukaba, which is controlled by a Nepalese contingent of the U.N. Force. He vowed that his force would move out "within 48 hours" to cover the remaining 25 miles to Tibnin.

In Beirut, a spokesman for the right-wing Christian National Liberal Party sought to disassociate the main-stream Christian militias from the anti-government action. He said the militiamen on the south were acting independently of party authority and blamed Israel for encouraging their attitude.

"Earlier the Israelis raised no objection to the army's move, but suddenly they sent word Monday that they were clearly opposed to the entry of the army in the south," he said.

According to Marijayoun residents, Maj. Haddad called an emergency meeting of his forces Sunday night, urging them to "resist this pro-Syrian army" and open fire if it tried to enter town.

[Reuter reported that in Beirut, at least nine persons were killed and 42 wounded in renewed fighting after a Syrian supply truck of the Arab League peacekeeping force came under fire from rightist militia in the Christian eastern sector of the capital.]

Prime Minister Selim Hoss said yesterday the army was recalling Haddad and another renegade Christian officer, Maj. Sami Shidiak to Beirut. It was the government's first move to deal with the controversial officers, whose cooperation with Israel has aroused the ire of the Syrians, Palestinians and Lebanese leftists.

Diplomatic sources said if the two disobey the order, which seems likely given the apparent open revolt against the army deployment, the government plans to court-martial them in absentia and strip away any remaining appearance of their legitimacy.

"Let's face it, one Western diplomat said, "this eight-kilometer belt they control down there is Israeli.These guys are run by the Israelis, and for all practical purposes there is still an Israeli presence in south Lebanon."

When Israeli forces withdrew from the area following their March invasion, they turned over a key "security belt" to the Christian rightists instead of to the U.N. force.

Aside from the militiament's opposition, ther seemed to be wide popular support for the army's move to the south. All along the route from the eastern Bekaa Valley, cheering townspeople welcomed the battalion's passage and showered it with rice and flowers. Carried away by the joyous mood, the soldiers sang and even danced in the street with the villagers.

But when the troops reached Kaukaba, the party ened. Now they faced a challenge that diplomats said could delay the dispatch of additional units for the army's first major operation since Lebanon's 1975-76 civil war.