The top leadership of the Soviet military establishment, including the defense minister and the Air Force and Navy chiefs, arrived here on a visit today amid speculation that the Kremlin wants to scuttle India's program of buying more of its weapons from the West.

The government of Prime Minister Indira Gandhi has tried to play down the six-day visit of Defense Minister Dimitri Ustinov and his entourage of nearly 30 generals as routine. But Indian sources noted that it is the largest high military delegation the Soviet Union ever has sent outside the Eastern Bloc.

In briefings for Indian correspondents, the Gandhi government has insisted that no new arms deals will be struck with the Soviet Union as a result of Ustinov's visit.

But that has only served to fuel speculation even more, as both Indian experts and Western diplomats expect Ustinov to offer New Delhi some of the Soviet Union's latest weapons--including the T82 tank used by frontline Soviet troops in Europe and the Mig27 interceptor and ground attack fighter.

Both of those weapons are far ahead of anything currently available on the Indian subcontinent.

Ustinov, 73, fanned that view on his arrival this morning when he replied to a question about the U.S. sale of F16 fighters and other weapons to Pakistan: "I would like to emphasize that no one on the Indian side can complain about the Soviet Union's friendly relations with India in the field of defense."

The Soviet Union started supplying weapons to India 20 years ago and has become the largest arms source for this country.

In 1980, Moscow and New Delhi concluded their biggest arms deal, a $1.6 billion Indian purchase whose real value is considered three to four times greater because the Soviets offered cut rates and soft terms that are far better than those available from the West.

The Gandhi government, however, stung by charges that it is under Moscow's influence as a result of the arms supply relationship, has been attempting to diversify its source of weapons.

It purchased Jaguar deep-penetration fighters from Britain and four submarines from West Germany. India is negotiating with France to buy Mirage 2000 fighter-bombers.

According to widespread reports here, the Soviets are trying to kill the Mirage deal although Indian Defense Minister Ramaswamy Venkataraman denied to Parliament that Moscow was pressing India to buy the Mig27 instead.

The Gandhi government appears to be sending signals to Western diplomats that it plans to resist the Soviet pressure, even though it feels that the United States' rearming of Pakistan is pushing India closer to the old reliance on Moscow for weapons that it wants to change.

The big question here, though, is whether Ustinov will offer India so sweet a deal that it will not be able to say no.

Whether India signs a new arms deal or not, it appears that it will press the Soviets to speed the supply of spare parts for tanks and planes it has already purchased, and to help improve this country's defense production facilities.

India manufactures Mig21s under license but would like to begin producing Mig23s, a more modern plane.

It was announced today that the chief of the Soviet aircraft industry, S.I. Silaev, has spent the past five days at the headquarters of India's fledgling aeronautics industry in Bangalore.

Venkataraman reportedly told Ustinov during their meeting today that New Delhi appreciated Moscow's help in improving India's defense production capability and expressed confidence of continued cooperation.

According to Indian sources, Moscow suggested the visit and has embarrassed the Gandhi government by persistently playing it up as a major event in Indian-Soviet relations.

Yet, the Indians pulled back their air chief, Air Marshal Dilbagh Singh, from a long-planned trip to Britain, and Army Chief-of-Staff K.V. Krishna Rao postponed a trip to Paris so that both service heads would be here for at least part of the Ustinov visit.

Ustinov, moreover, is staying at Rashtrapati Bhawan, the former British viceregal residence usually reserved for visiting heads of state.

Further underscoring the attention he is getting here, Ustinov met for an hour this afternoon with Gandhi, accompanied only by their translators.