Polish and Roman Catholic Church officials have reached an agreement in principle on establishing an agricultural development fund that would channel financial assistance from western sources to private farmers in Poland, according to informed sources.

The idea of such a church-directed program was affirmed by Vatican and Polish Communist authorities during the visit last week of Pope John Paul II, the sources said.

Polish church officials had been promoting the plan since last year to provide a lifeline to the country's struggling farmers, but Communist officials had been cool to a fund that would make the agricultural sector more independent of the state. About 80 percent of Poland's farmland is privately owned, an anomaly in the Soviet Bloc where collectivization of agriculture is the norm.

In a toughly worded sermon on June 2, Polish Cardinal Jozef Glemp complained about government foot-dragging on the fund proposal. Four days later, Glemp, in a meeting with Polish leader Gen. Wojciech Jaruzelski was reportedly informed of the government's willingness to move ahead with the project. Jaruzelski and the pope are said to have discussed the matter when they met.

Word of the new fund is the most concrete church-state development to filter out from the papal visit. The weeklong pilgrimage of the pope to his homeland has left a wake of rumors and contradictory reports, turning largely on the future of Lech Walesa, leader of the banned Solidarity union, who met privately with John Paul on the pontiff's final day in Poland.

Glemp and senior bishops from the five principal cities on the pope's itinerary will go to Rome later this week to report to John Paul on the political and social repercussions of his visit, according to Vatican sources and press accounts in Rome.

Diplomatic observers in Rome told Washington Post correspondent Michael Dobbs that the speed with which the consultations had been arranged suggests that the pontiff intends to play a very active role in moves toward national reconciliation here.

Vatican officials discounted speculation that John Paul, in return for new church privileges from the Polish government and the promise of an easing of the repression of Polish society, agreed to urge Walesa to stop his political activities.

Speculation that the pope had made such a deal was fueled by an article last week in the Vatican newspaper L'Osservatore Romano that said Walesa "has lost his battle" and declared that the "sacrifice of inconvenient individuals" was sometimes necessary to promote the well-being of the community.

But the day the article appeared, its author, the Rev. Virgilio Levi, the paper's deputy editor, was forced to resign, reportedly as a means of distancing the church hierarchy from his opinions.

The resignation suggested either that Levi had been too blunt in stating a difficult truth the pope had not wanted disclosed or that he had been terribly off the mark. He has since said that he was expressing his own private views.

Walesa has given few details of his meeting with the pope, which Polish authorities had reluctantly agreed to allow. The government contends that Walesa is now merely a private citizen with no political role.

Both the Catholic Church and the Polish state have expressed satisfaction with the papal visit. Huge crowds attended papal masses where John Paul endorsed the ideals of the now-banned Solidarity movement and counseled faith and self-determination as a means toward eventual Christian victory.

Jaruzelski, in turn, managed through two meetings with the pope to reinforce the impression of church cooperation with his regime. But the suggestion that he has granted new concessions to the church has created problems for Jaruzelski within his Communist Party.

While the government in its first post-visit pronouncements has sought to cast the pilgrimage in a positive light, final judgments have been reserved for later, presumably to give Jaruzelski time to deal with the objections of party hard-liners here and in Moscow.

As originally conceived, the money from the West was to be channeled largely under church auspices to provide grants and subsidies to Polish farmers for the purchase of equipment, supplies and feed for livestock. But the church is expected to yield some control, possibly agreeing to the funneling of funds through Polish state institutions.

Early drafts of the plan called for an outlay of about $2 billion. Cardinal John Krol of Philadelphia, who was in Poland during the papal visit, described for CBS television yesterday a five-year plan to establish a $5 billion church bank but no other sources mentioned such a large figure. Krol said the bank would receive half its funding from European governments, 25 percent from the Vatican and 25 percent from private foundations, including the Rockefeller Foundation.

Richard W. Lyman, president of the Rockefeller Foundation, said in New York that while the foundation last year funded an assessment of Polish agriculture "with special attention to the problems facing farmers," it was "not in a position to undertake large-scale funding for efforts to help the Polish people."