HAVANA --- Pope John Paul II will deliver a message to Cuba's youth Friday at a Mass in the town of Camaguey.

Later in the day, the pontiff will meet with Cuban cultural leaders at the University of Havana.

On Thursday, Pope John Paul II went to the center of Cuba's communist regime, meeting President Fidel Castro at Havana's Palace of the Revolution just hours after attacking one of his proudest achievements --- the state education system.

Castro personally greeted the 77-year-old pontiff, who also criticized communism during an open-air Mass in the central city of Santa Clara earlier in the day.

But there was no sign of repercussions from the pope's outspoken statements when he met Castro. The Cuban leader courteously led the pontiff along the palace's corridors, chatting warmly, before and after their 40-minute private meeting.

No details were available on the substance of their conversation, although the pontiff said during his flight from Rome Wednesday that he wanted to talk about human rights, hear ''the truth'' from Castro on Church-state relations, and press for Christmas to be made a permanent holiday in Cuba.

Castro, 71, declared Christmas Day a holiday last year in honor of the pope's visit but it is usually a normal work day.

Chief papal spokesman Joaquin Navarro-Valls said the Vatican had relayed appeals for clemency by "many'' prisoners to Cuban government, which Navarro-Valls said received them "with great attention''. Asked if any of the prisoners were political, he said, "I think there are all kinds.''

In Santa Clara, 180 miles east of Havana, the pope celebrated his first Mass on Cuban soil earlier Thursday and lost no time in criticizing communism, saying it could not replace Christianity.

"No ideology can replace his (Christ's) infinite wisdom and power,'' the pope said, adding: "There is a need to recover religious values at the level of the family and of society.''

He added: "Do not be afraid; open your families and schools to the values of the gospel of Jesus Christ, which are never a threat to any social projects.''

In an address that centered on family values, he lamented what he called "an acceptance of abortion, which is always, in addition to being an abominable crime, a senseless impoverishment of the person and of society itself''.

But his strongest criticism was reserved for the educational system.

Without naming them, he referred to the island's rural boarding schools, which almost all Cuban adolescents are obliged to attend from age 14.

The pope said they often caused "traumatic'' separation between parents and children. Such experiences put young people in situations that resulted in "the spread of promiscuous behavior, loss of ethical values, coarseness, premarital sexual relations at an early age and easy recourse to abortion''.

"All this has a profoundly negative impact on young people,'' the pope said. His comments struck right at the heart of one of aspects of the Cuban revolution of which the government is most proud --- its free and universal education.

In his welcoming speech for the pope Wednesday, Castro listed education as one of the main achievements of the Cuban revolution.

The rural schools are dreaded by some parents, who would prefer to keep their offspring under their control for a few more years and complain that the relaxed co-ed environment leads to early and casual sex, and to unwanted teenage pregnancies.

The pope also openly urged a liberalization of education to allow a place for religion in Cuba, where all Church schools were nationalized in the early 1960s.

The pope's outspoken attack in a nationally televised Mass was all the more extraordinary in a country where all media is state controlled and where criticism is usually confined to Cubans grumbling in their homes, or to dissidents.

The pontiff, walking with a stick, rode to and from the meeting with Castro on the palace's second floor chambers in an elevator, rather than having to negotiate the grand main staircase as is customary for visiting foreign dignitaries.

After their meeting, Castro presented the pontiff with a leather-bound 19th century book on the life of Cuban Roman Catholic priest Felix Varela, who is honored as an intellectual precursor of Cuban independence and is a candidate for sainthood.

Castro also gave him a medal of the order of Varela, Cuba's highest honor for cultural merit.

The pontiff gave Castro a large reproduction of a Vatican mosaic icon depicting Christ.

© Reuters Ltd.