Chan: Al Qaeda leader Osama bin Laden has accused the Pope of being involved in the publication of cartoons of the Prophet Mohammed. Bin Laden says Europe would be punished for the cartoons, which unleashed a bloody reaction after other newspapers around the world reprinted them. The traditional holy Thursday mass in St. Peter's Basilica contained an extra message this year. The Pope used the occasion to urge priests around the world to be strong in the face of criticism. [Pope Benedict XVI, Bishop of Rome]: "The priest must stand upright, fearless and ready to withstand even insults for the Lord's sake, as the 'Acts of the Apostles' say: "They must be happy to have suffered insults for their love for the name of Jesus." His comments came a day after the al Qaeda leader Osama bin Laden made scathing accusations about the Pope. He linked him to the publication of cartoons of the prophet Mohammed - printed in a Danish newspaper three years ago. [Osama Bin Laden, Al Qaeda Leader]: "Then came your publishing of these drawings, which came in the framework of a new crusade in which the Pope of the Vatican has played a large, lengthy role." The publication of the cartoons sparked protests around the world. And this new message - bin Laden's first since November - also threatened the European Union with grave punishment over the issue. He said Europe was Testing Muslims and [Osama Bin Laden, Al Qaeda Leader]: "the answer is what you see and not what you hear." Bin Laden's attempt to stoke Christian-Muslim tensions also coincides with next week's release of a controversial film. It's been made in Holland by a right-wing politician who has called the Koran a "facist" book. The Dutch have increased security in anticipation. But the Pope clearly has no plans to change his Easter itinerary following the accusations, which the Vatican described as "totally unfounded."