Nicaragua offered in recently suspended talks with the United States to accept a U.S. military presence in Central America, Nicaraguan officials and other knowledgeable sources said this week.

Nicaragua proposed a reduction in the number of U.S. military advisers and the size of U.S. military maneuvers in the region, and it was unclear whether it would have insisted on keeping some of its own Cuban military advisers in return for endorsing a U.S. presence. But the offer represented a softening of Nicaragua's previous position, stated in a proposed regional peace treaty, calling for an end to any foreign military presence in Central America.

The United States broke off the talks despite this sign of flexibility because it rejected Nicaragua's insistence that the negotiations lead to a bilateral, U.S.-Nicaraguan agreement, according to officials and diplomats here and in Managua. The United States stuck to its longstanding position that Nicaragua instead should reach an agreement with its Central American neighbors in the regionwide peace talks known as Contadora.

Given the U.S. stance, Nicaragua's demand for a bilateral accord contributed to the breakdown in the talks, officials said. Even Mexico, which sympathizes with the Nicaraguan government and hosted the negotiations at the Pacific resort of Manzanillo, privately was unhappy with Nicaragua's stubbornness regarding this issue, they said.

The Nicaraguans may have pursued a bilateral accord despite repeated U.S. rejections because they mistakenly believed that Washington would soften its anti-Nicaraguan policies in President Reagan's second term, according to two sources. This idea, widely held in Central America from November through mid-January, drew strength primarily from reports of the planned replacement of several U.S. policy makers viewed as hard-liners including Jeane J. Kirkpatrick, ambassador to the United Nations.

While Nicaragua may have misplayed its hand, the United States was mostly to blame for the breakdown in the talks, according to officials from several countries, including U.S. allies. The suspension prompted critics to renew charges that Washington opposes a negotiated settlement with Nicaragua and that the United States entered the talks in June only as a ploy to portray President Reagan as a peacemaker in an election year.

U.S. allies, including West Germany and Spain, publicly criticized Washington's withdrawal from the negotiations, and British Prime Minister Margaret Thatcher signaled sympathy for Nicaragua by meeting this week for the first time with a senior official of the left-wing Sandinista government. She received Nicaraguan Vice President Sergio Ramirez in London.

"The Americans don't want an agreement in Central America that would give the Sandinistas any political space. The policy seems to be to punish Nicaragua," said a senior diplomat who represents a U.S. ally in the region.

The two top negotiators in the eight rounds of Manzanillo talks were U.S. special envoy for Central America Harry Shlaudeman and Nicaraguan Deputy Foreign Minister Victor Hugo Tinoco. Details regarding the talks have begun to emerge since Washington suspended them Jan. 18. Previously both sides had respected an agreement to keep the substance of the negotiations secret.

The Manzanillo talks, like the Contadora ones, raised the possibility of a trade-off between Nicaragua and its conservative neighbors allied with Washington. Managua wanted the United States to drop support for Nicaraguan antigovernment rebels with bases in Honduras and Costa Rica, and to end military activities in Central America aimed at intimidating the Sandinistas. Washington wanted Nicaragua to drop support for Salvadoran left-wing guerrillas, trim its armed forces, reduce ties to the Soviet Bloc and promote democracy at home.

The turning point in the talks came in September when Nicaragua announced its willingness to sign the latest draft of a Contadora treaty. The United States opposed that pact, and persuaded its Central American allies to do so as well in part because the draft called for eventual withdrawal of all U.S. military personnel from the region.

The Sandinistas, believing that U.S. opposition had killed prospects for a Contadora deal, pressed hard at Manzanillo in November and December for a U.S.-Nicaraguan treaty. As an enticement they offered to accept U.S. military advisers and maneuvers in the region, although on a reduced scale, according to Nicaraguan Foreign Ministry First Secretary Alejandro Bendana and other officials.

The United States rejected a bilateral accord, saying that the Manzanillo talks only could pave the way for a Contadora agreement, U.S. officials said. Now that the Manzanillo talks have been suspended, however, the Nicaraguans have hardened their position publicly and maintain that they must stick to the original Contadora proposal calling for gradual withdrawal of all foreign military advisers and a ban on foreign military maneuvers.

A Latin American agreement such as Contadora, they say, cannot formally endorse Washington's right to a military presence in the region.

"The essence of the problem is that Contadora challenges the Monroe Doctrine. It challenges the United States' God-given right to a military presence in Central America," Bendana said. Other observers expressed doubt, however, that the Sandinistas would insist in the Contadora talks on points on which they had yielded at Manzanillo.