They are two of the most admired religious leaders in the world but Pope Francis has chosen not to meet the Dalai Lama in Rome this weekend when the Tibetan exile attends a summit of Nobel Peace Prize winners.
The decision reflects an acute diplomatic dilemma for the Pope, at a time when the Vatican is attempting to improve its relations with Beijing and wants to avoid upsetting the Chinese authorities for fear of provoking trouble for the country's Catholic community.
The snub is hardly in keeping with the Argentinean pontiff's enthusiasm for dialogue with other religions, an agenda he has pursued in recent months on trips to Turkey, Albania and the Holy Land.
He will pick up the theme next month when he travels to Sri Lanka, where he will meet the island's Buddhist leaders.
"This time I won't meet Pope Francis," the Dalai Lama on Wednesday after arriving in Rome, adding that he would have been "very happy" to do so.
"The Vatican administration says it's not possible because it could cause inconveniences."
The Vatican confirmed that the two men, whose shared concern for the poor and the down-trodden give them much common ground, would not meet.
"Pope Francis obviously holds the Dalai Lama in very high regard but he will not be meeting any of the Nobel laureates," a spokesman said.
Instead the South American pontiff will send a video message to the conference of Nobel Peace Prize winners.
The event was originally due to be held in South Africa but had to be moved after the Pretoria government refused to issue the Tibetan spiritual leader a visa, fearing repercussions from Beijing.
Under Pope Francis, the Holy See is trying to improve its previously fraught relations with China.
When he visited South Korea in August, he became the first pontiff ever to be allowed to fly through Chinese air space.
In a radio message he sent his “best wishes” to Xi Jinping, the Chinese president - it is customary for the Pope to send greetings to every country that he flies over when travelling abroad.
His greeting, however, came during one of the most intense campaigns of repression for Chinese Christians, with authorities destroying churches or removing their crosses.
The Dalai Lama is often snubbed by leaders anxious not to offend Beijing. The last time he was granted a papal audience was with Benedict XVI in 2006.
There are an estimated 12 million practising Catholics in China.
Half of them belong to a state-sanctioned Church while the other half attends clandestine churches which swear allegiance to the Vatican.