Argentine officials greeted Secretary of State Alexander M. Haig Jr. here tonight while expressing little hope for a quick resolution of the confrontation with Britain over the Falkland Islands. Sources close to the military hierarchy suggested that the United States had tilted toward the British position.

Haig, after a 16-hour flight from London, underlined that "Argentina and the United States are hemispheric partners" and said "that relationship, which has become more cordial in recent months, should serve as a good basis in seeking a diplomatic solution."

In an arrival statement, Haig said the basis of his mission was the U.N. resolution calling for immediate withdrawal of Argentine troops that occupied the Falklands a week ago. The Argentine sources close to high-ranking military officers here specified the U.S. role in passage of that Security Council resolution as evidence of Washington leaning to the British.

Haig is to talk with President Leopoldo Galtieri and Foreign Minister Nicanor Costa Mendez on Saturday. The U.S. delegation is scheduled to leave for Washington Saturday night.

Argentina's military government is expecting Haig to present a tough British position, including the demand that Argentina withdraw its troops from the islands before formal negotiations over the conflict can begin. Officials here said that Argentina is unwilling to do so unless its sovereignty on the South Atlantic archipelago is recognized.

Sources here also said that while Argentina stands officially willing to negotiate all other aspects of the Falklands' future administration, the government is unlikely to accept a formula, reportedly discussed by Haig with British Prime Minister Margaret Thatcher, that would involve British lease of the territories or a joint Argentine-British administration.

Having quickly incorporated the 200 islands of the Falklands as a new Argentine province and installed a military government this week, the military government here cannot now easily agree to demands for British rule of the islands, officials said.

The most that Argentina is inclined to consider, they added, is a mixed formula for administration of the territory, perhaps involving representatives of the United Nations or citizens chosen from among the Falklands' 1,800 residents, most of whom are of British descent.

The Argentine foreign minister said last night that the U.S. delegation "would be listened to." He avoided criticism of the U.S. backing for Britain in the United Nations by saying that "it is erroneous to think the United States would abandon its allies of Europe."

Nevertheless, high military officials here are reported to be angry over what they perceive to be the heavy U.S. tilt toward Britain in the dispute and have argued that the Galtieri administration's policy of building close ties with the Reagan administration--in contrast to Argentina's often aloof stance--has backfired.

"Everyone expected the United States to be against Argentina in this crisis but not in as forceful or open a way as it has been," said one Argentine political source. In particular, officials privately accuse the Reagan administration of tilting the votes of countries such as Zaire and Jordan against Argentina in the U.N. Security Council's condemnation of the invasion.

Although the United States has striven to present itself as an impartial mediator between its British allies and newly friendly Argentina, there are perhaps inevitable rumblings in both countries that Washington has not lived up to the level of friendship each has expected.

Argentina still is hoping the United States will prevent Britain from launching military attacks on Argentine forces in the South Atlantic. But officials here have subtly indicated in recent days that Buenos Aires may consider reversing its diplomatic alliances over the Falklands issue if it is not resolved satisfactorily. This could mean cooling the U.S.-Argentine relationship in favor of a more traditional neutral stance, or even strengthening ties with a recently more important trading partner, the Soviet Union.

Although Argentina has one of the world's most staunchly anticommunist governments, it has established close economic ties with the Soviet Union and this week has consciously played up the signing of several important commercial agreements with the Soviets as a kind of warning to the West, sources said.

Argentina, which already sells more than 80 percent of its grain exports to the Soviet Union--or some 15 million tons last year--yesterday signed a new accord for the purchase of Soviet industrial machinery. It imported $67 million worth of Soviet goods in 1981.

Earlier this week, Argentina also signed an agreement to import 100 tons of Soviet enriched uranium and heavy water for South America's most advanced nuclear program, and officials said yesterday that the two countries are studying the possibility of forming joint enterprises for krill fishing in the South Atlantic--including in the waters around the Falkland Islands.

Despite these accords and Argentina's apparent irritation with the United States, the prospects of a political move by the miitary here toward the East was hampered when the Soviet Union failed to veto the U.N. resolution condemning Argentina, as the government here had expected, sources said.

While continuing to leave open its diplomatic options, the military has also moved to counter Britain's threats of force with an equally impressive show of militance. Gen. Galtieri indicated to reporters last night that Argentina could attack if confronted with a British blockade of the islands, and the armed forces command continued to summon reserves and draftees newly released from the military to recruitment offices today.

Troops have been airlifted from Argentine bases to the southern port of Comodoro Rivadavia, where military operations are being carried out, along with a shuttle service to the Falklands, 400 miles to the southeast.

In Washington, the Defense Department announced that U.S. merchant ships had been advised to stay away from the 200-mile restricted zone around the islands that Britain declared effective Monday, but said the notice "in no way constitutes" U.S. policy in the dispute, The Associated Press reported.

Government officials appeared to be encouraging a mass rally that has been called for Saturday outside the presidential palace where Haig is to meet with Galtieri and Costa Mendez.