ROME -- Pope John Paul II celebrated mass in St. Peter's Square on New Year's day Monday during which he called for a dialogue between different cultures.

Such a dialogue was not easy despite the development of modern communications, the pontiff said, but it was the only way to achieve peace in the new millennium and an "authentic culture of solidarity and justice".

In his Angelus prayer in St. Peter's Square the Pope called on Israel and the Palestinians to press ahead with peace talks, saying: "Especially at this time, we should be thinking of the holy land."

The pontiff looked weak and seemed to struggle with his speech, which was sometimes unclear because of his Parkinson's disease. Vatican sources said his health has deteriorated.

Earlier Monday the Pope called for peace and justice in Christianity's third millennium as he rang in the New Year shortly after midnight by addressing the world from St. Peter's Square.

The new chapter in the Christian calendar must bring with it an "historic change", the 80-year-old pontiff told tens of thousands of people from the window of his Vatican apartment.

He said the previous years had been filled with "dramas and hopes, joys and suffering, victories and defeats" and he prayed for a more caring world in the new millennium.

"I hope that the new millennium brings all nations peace, justice, brotherhood and prosperity," he said. (DPA)