A weary but smiling Pope John Paul II returned home safely today at the close of a 10-day trip to Ireland and the United States that established him as a major world figure but also underscored the conservative direction of his papacy.

The pope arrived at Rome's Leonardo da Vinci Airport this morning to a greeting by Italian Prime Minister Francesco Cossiga, 20 cardinals and Rome's new, hard-line communist mayor, Luigi Petroselli.

Before boarding an Italian Army helicopter for the short flight to Vatican City, the pope told the 2,000 people at the airport that his six-city tour of the United States and his contact with the American people had left him with "the desire for an even more direct and familiar contact with these dearest children."

The pope later left the Vatican by helicopter for the papal estate at Castel Gandolfo in the Alban Hills south of Rome. Vatican officials said he would rest there until Wednesday.

At the Rome airport, the pope said the United States is "a great country to which certainly corresponds an immense role and a great responsibility -- because of its high level of welfare and technical progress -- in the construction of a just world worthy of man."

He said that his three-day visit to Ireland at the outset of the trip had permitted him to pray "for peace and reconciliation for this beloved island." He added that his Oct. 1 address to the United Nations' General Assembly indicated the Roman Catholic Church's intention to continue its efforts to promote peace, justice and human rights.

Upon arrival at the Vatican in the heart of ancient Rome, the pope made a brief appearance at the window of his private study to greet a crowd of several thousand tourists and pilgrims in Saint Peter's Square.

"I am back, I am back," he told them, adding that he was grateful "for the providence which has guided me in these days and which has brought me back to Rome."

Vatican officials said the pope met privately with members of the Vatican Curia at St. Peter's Basilica before he spoke to the crowd.

After leaving Washington, they said, the pope immediately went to his compartment in the chartered Boeing 747, ate the first course of his meal and fell asleep.

The officials said he ate caviar, salmon, pate and shrimp and drank three glasses of wine before going to bed as the plane flew him home.

The enthusiastic reception given the pope by the more than 10 million persons estimated to have heard him speak during his 10,000-mile trip to Ireland and the United States has led many observers here to conclude that, a week before the first anniversary of his reign, John Paul II has emerged on the world scene as a leader of major stature.

But Vatican sources here also believe that the content of many of the pope's speeches, particularly during his visit to the United States, is likely to produce a backlash from church progressives.

Before the pope's Sept. 29 departure on a papal tour of unprecedented breadth, many Vatican observers here had speculated that the trip might provide important clues to the nature of the papacy that began with his election Oct. 16, 1978.

During the week he spent in the United States, the pope repeatedly reconfirmed traditional church policy on controversial issues such as priestly celibacy, birth control, abortion, divorce and the elevation of women to the priesthood.

"It's not entirely a surprise, and there's still a lot we don't know about how he will reorganize the Vatican and what role he will give the church's bishops," said one Roman Catholic progressive.