As the Pope celebrates his eighty-second birthday, there have been renewed concerns about his health and speculation that he might retire.

Special birthday greetings

His official spokesman insists that he will soldier on.

But the decision to have the Pope only read the beginning and the end of a speech before an audience of thousands of children in Rome will no doubt fuel more speculation.

Occasionally, assistants do read the Pope's speeches, especially if they are in languages he finds difficult.

But the Pope normally reads remarks in Italian, such as Saturday's speech, himself.

Reuters news agency reported that the arrangement appeared to have been agreed upon in advance, and was not caused by any new worsening in the Pope's health.

"Thank you very much for your greetings," the Pope told the crowds of children, who sang Happy Birthday to him.

Polish pilgrims

The Pope also received birthday greetings at a special Vatican audience with 7,000 pilgrims, many of them from his birthplace, Poland.

The Pope is set to resume foreign travel

In recent months, John Paul - one of the longest-serving popes in history - has become increasingly immobile.

His speech is often slurred, and his face mask-like, the result of Parkinson's disease.

He is in almost constant pain when he walks and may have to take to a wheelchair.

Yet he continues to receive bishops and visiting dignitaries most days at the Vatican.

Foreign travel

Next week, he is due to resume his foreign travels after a gap of eight months.

On Wednesday, he will travel to the former Soviet republic of Azerbaijan and to Bulgaria.

Later in the year, he is planning to visit Canada, Mexico and Guatemala, and also his native Poland in August.

Two senior cardinals have hinted this week that the Pope might consider stepping down if his health declines to the point that he becomes incapacitated.

Traditionally, once elected, a pope serves for life.

No pope has resigned in modern times, although there is now a provision in canon law - the law of the Roman Catholic Church - which states that he can resign if he wishes.

In this case, a conclave would be held and a successor elected by the College of Cardinals, all of whom now have to be under 80 years old to vote - two years younger than the Pope.