Perhaps only in U.S.-Indian relations could the subjects of nuclear fuel and rhesus monkeys end up on the same bargaining table.

When President Carter and Indian Prime Minister Morarji Desai confer at the White House today, there will be few other contentious issues of major importance to occupy their time.

They are likely to talk in general terms about the shift in government in Afghanistan, the death sentence hanging over Pakistan's former prime minister Zulfiqar Ali Bhutto and the course of U.S.-Soviet relations. But it is India's need for nuclear fuel that will lead to the most earnest discussion.

Well-informed U.S. officials say there is also a possibility that India's search for a new generation of deep-penetration strike aircraft could come up. British and French planes are in contention in the $2 billion deal, but one U.S. official commented yesterday, "One would think there are better ways to spend $2 billion in South Asia."

And, of course, there are the rhesus monkeys - vital to American laboratories that produce critically needed serums and vaccines but recently banned for export by India for religious reasons.

The United States, revitalizing its crusade for nuclear nonproliferation, has decided it no longer will ship nuclear fuels after 1980 to any country that does not open its nuclear plants for international inspection, and India does not open all of its facilities.

It is Desai's apparent goal while in the United States to convince the American people, and specifically Congress, that his vow not to produce nuclear weapons is a sincere of a nation that merits the attention of U.S. policy makers.

Carter's according to those who follow U.S.-Indian relations closely, hopes to win Desai, and through him the nonaligned bloc, over to the U.S. view of Soviet foreign policy intentions, not to mention the president's strong beliefs in controlling nuclear weapons.

Desai's task is not an easy one, for reasons that say much about Americans and their view of the world.

At 82, Desai is one of the most durable of the world's political leaders. Yet, because of personal beliefs and because of Indian culture is so vastly different from anything most Americans know, he is viewed by many as an eccentric.

After all, the casual observer points out, here is a man who has been celibate for more than 40 years, has a diet consisting mostly of fruit, yogurt and nuts, and who drinks his own urine each morning. All three practices have a firm basis in Indian medicine or philosophic beliefs going back thousands of years, yet they appear exotic, to say the least, to most Americans.

Lost in these images of India is the fact that Morarji Desai was a state civil servant in British Indian before Jimmy Carter was born and that he was a fighter for Indian independence behind the banner of Mahatma Gandhi when Carter was still a toddler in Plains.

Before Carter became president, Desai had already been the equivalent of a state governor, a commerce minister, finance ministe and deputy prime minister.

Despite his history of almost half a century in Indian politics before he came to power as prime minister, it was only when his Peoples Party crushed Prime Minister Indira Gandhi at the polls 15 months ago that attention began to focus on this ascetic, determined political leader.

Now it is the nuclear issue, and Carter's warning during his visit to New Delhi in January of a "cold, blunt" letter outlining U.S. demands for inspection, that draw most attention in U.S.-Indian relations.

"Cold and blunt" got transformed into "straight and frank" by the time the letter was written, and Carter has overruled the Nuclear Regulatory Commission to allow shipment of fuel on a short-term basis. Congress still has a chance to veto the deal under the recently passed Nuclear Nonproliferation Act. Unless the provisions of the act are changed or India changes its policies, the shipments now under discussion will be among the last.

Desai's position has been consistent: India has no intention of building a nuclear weapon and it will not open all its plants to inspection until the superpowers open theirs. Why, he asks, should it be the "have-nots" who knuckle under when it is the "haves" who are in a position to do the most damage?

It is an argument that goes down well at home. Indira Gandhi may have alienated millions of voters with such programs as enforced sterilization, but India's explosion of a nuclear device and its "defiance" of superpower pressures brought cheers.