Cuban President Fidel Castro allowed 46 political prisoners to fly to Miami yesterday and said that he hopes to release most of the remaining political prisoners by January.

Miami banker Bernardo Benes, a Cuban exile who negotiated details of the flight with the Cuban government, said Castro told him in Havana yesterday that he hoped to free "most of the political prisoners by the 20th anniversary" of his takeover, which will be celebrated Jan. 2.

Castro said last month that about 3,000 prisoners remained in jail for crimes against the state.

A reporter who said he attended the same meeting with Castro yesterday quoted the Cuban president as saying that "if all goes well" he will release most of the prisoners by the end of this year.

Castro's plan would go beyond his initial gestures, which began with a Sept. 6 news conference at which he proposed a dialogue with representatives of the Cuban exile community, which numbers about 45,000 in the Miami area alone. Most left Cuba since Castro's 1959 takeover.

Benes accompanied the ex-prisoners on their 38-minute flight to Miami, where they were taken directly by bus to an emotional reception by 2,500 exiles at the Decade County auditorium.

The standing ovation as they entered the hall grew loudest for Antonio (Tony) Cuesta, the best-known of the group, who was captured in 1966 during an infiltration mission. Blind and one-armed, he was guided into the hall by his wife one month.

Cuesta said he would work for the release of those still in Cuban prisons. It was an emotional scene in the auditorium as the ex-prisoners embraced relatives and friends they had not see for years.

Reports on the number of relatives who accompanied them on the flight ranged from 25 to 33.

In an interview, Benes criticized those exiles who opposed his negotiations or any other dealings with the Cuban government. He said that Castro seemed intent on releasing prisoners and that this objective, along with the reunification of families, should be pursued.

Castro's offer has produced a pririted debate among the exiles, whom Castro previously referred to as "gusanos," or worms. Hard-liners, including most of the tradition exile leaders, oppose any dealing with Castro on the theory that it would imply recognition or approval. Moderates argue for pursuing limited goals of freeing prisoners and reuniting divided families without giving up basic opposition to Castro's rule.

The authorities in Miami, fearing an unwieldy crowd and traffic jam at the airpost, barred the press and public from viewing in the plane's arrival. Instead, a coordinating committee of exiles and representatives of the Roman Catholic archdiocose arranged for three buses to pick up the Cubans at planeside and take them, with a police escort, to the 2,501 seat Dade County Auditorium for welcoming ceremonies.

Hours before the reception, exiles began arriving at the auditorium, which ordinarily houses the Florida Philharmonic, opera performances and other presentations. An emotional scene was inevitable as relatives caught their first sight of each other in years.

"I think that is's an important victory for human rights and prisoners of conscience," said Msgr.Bryan Walsh, director of the Catholic Service Bureau in Miami and a coordinator of the reception.

Six Cuban exiles traveled on the chartered plane to Havana. They said they carried a writter message to the Cuban government, suggesting ways of continuing the dialogue about further releases and reunification of families.

Among the six was Benes, who was disclosed in the last few days to have been the principla exile negotiator for the release of this first group. Benes had shuttled between Miami and Havana for intermittent talks. About 20 exiles picketed his bank Friday, protesting his role.

The State Department announced Oct. 13 that 46 prisoners and 25 relatives had been approved for immigration by Attorney General Griffin B.Bell. The announcement followed a six-week screening to make sure there were no spies, terrorists or "common criminals" among them.

Cuban submitted the original list to the U.S. government for approval. The list included 48 prisoners, but two did not appear for screening. Additional lists have been submitted, virtually assuring further departures of ex-prisoners and their families.

Asked at his September news conference how many present and former prisoners would be allowed to emigrate, Castro replied, "Well, there might be over 1,000. There might even be 2,000, 3,000. We've set no limits on that."