Reversing its previous stand, Vietnam has informed the United States that it is ready to establish full diplomatic and trade relations without insisting that the United States agree in advance to supply aid to reconstruct that war-ravaged country.

Vietnam's growing eagerness for U.S. ties of all kinds - expressed in public and private statements of Hanoi's diplomats, an "unofficial" discussion with U.S. officials earlier this month in Honolulu and invitations to American congressional and business groups - has been greeted warily by the Carter administration.

In the view of some policy-level officials, the last thing the White House wants right now is another controversial foreign policy move, such as the exchange of ambassadors with Hanoi.

Officials are also hesistant to permit relations with Vietnam to get ahead of normalization of U.S. relations with the People's Republic of China, which is locked in conflict with its former ally and southern neighbor.

Despite Vietnamese requests for a meeting "at any time and in amy place," the State Department has no plans for early resumption of diplomatic talks, which last took place in Paris in December 1977, now that Hanoi has virtually accepted the U.S. position on the normalization of relations. Some State Department officials suggest that a new diplomatic meeting is unlikely before the congressional elections in November.

In what appears to be an effort to postpone the Vietnam relations question, recent discussions between the State Department's area director for Indochina, Frederick Z. Brown, and two senior officers of the Vietnamese Foreign Ministry in Honolulu are being described here as "unofficial chats," and the State Department continues to maintain that it has not been told formally and directly that Hanoi has dropped its previous conditions for normalization of relations.

The Hanoi officials were in Honolulu accompanying a Vietnamese graves registration team, which visited the Defense Department's Central Identification Laboratory and Joint Casualty Resolution Center in an effort to aid in the identification of the remains of U.S. servicemen listed as missing in action during the war.

Vietnam's initiative in dispatching this team, after a five-month delay due to the spy charges and trials of Ronald L. Humphrey and David Truong and the expulsion of Vietnam's ambassador to the United Nations as a coconspirator, is one of several recent gestures toward the United States. Others include:

Hanoi's decision to release at least 25 ethnic Vietnamese who hold American passports, at the request of Sen. Edward M. Kennedy (D-Mass.). A team headed by a Kennedy aide, Jerry Tinker, is to leave Washington today to pick up these women and children in Hanoi and discuss the reuniting of other families divided by the war.Previously, Hanoi took the position that such humanitarian gestures would have to await the establishment of U.S.-Vietnamese diplomatic relations.

An invitation to a group of House members headed by Rep. G. V. (Sonny) Montgomery (D-Miss.) to visit Vietnam next month for talks about a broad range of bilateral questions. Montgomery said yesterday his team will consist of about 10 lawmakers of both parties and all shades of political opinion.

Invitations to the American Chamber of Commerce in Hong Kong, a Pan American World Airways delegation and other business groups to visit Hanoi. Some of the recent business visitors reported open and candid expressions of eagerness by Hanoi officials for commercial as well as diplomatic ties with the United States. Trade with Vietnam is now barred by a U.S.-imposed embargo.

A just-completed three-week journey through noncommunist Asia by Vietnamese Vice Foreign Minister Phan Hien produced repeated public statements as well as private statements to Asian diplomats that Hanoi is ready to move ahead toward normalization of relations with the United States without conditions. Hien emphasized that "we are now entering a new stage" in the U.S.-Vietnamese dialogue.

Vietnam is reported to have suffered serious economic setbacks due to a bad harvest, the forced departure of skilled and enterprising ethnic Chinese and the drain of the continuing war with Cambodia.

These factors, plus the growing confrontation with China, are believed to lie behind Hanoi's definite and unexpected drive toward diplomatic and trade relations with its former foe, the United States.