Pope sits out mass again

The Pope sat on his throne for most of the Palm Sunday mass

VATICAN CITY -- For the second time in less than a week Pope John Paul II, suffering from an arthritic knee, is to attend but not celebrate a major Holy Week mass.

A programme issued by the Vatican said that the 81-year-old pontiff would "preside" at a Holy Thursday mass later in the morning and read a sermon.

But the mass will be celebrated by a cardinal so that the pope can spend most of the time seated.

On Sunday John Paul did not celebrate Palm Sunday mass for the first time during his 23-year reign.

He sat through the two-hour mass, held the week before Easter Sunday, but allowed a cardinal to celebrate it.

Vatican officials said they would decide on a case by case basis between Thursday and Easter Sunday at which ceremonies the pope would be the main celebrant.

MORE STORIES Frail pope sits out Palm Sunday mass

Pain in his right knee has forced the head of the Catholic church to cancel several engagements in the past few weeks.

Celebrating full mass means the pope has to stand for up to two hours.

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The pontiff has missed services before due to health problems -- though only minor ones.

The Palm Sunday mass in St Peter's Square was said by Cardinal Camillo Ruini, the pope's vicar for the diocese of Rome, while the pope spent most of the time seated on his throne.

John Paul read the opening prayers at the ceremony from his throne. He also read the homily and some prayers.