Pope Francis is flying to South Korea today — and that means he'll be able to address China's leaders, as well. In what's seen as a sign of thawing relations, China is allowing the pontiff to use its airspace. The Vatican hasn't had formal relations with China since 1949, when the communists took charge.

"The fact that he is being allowed to cross Chinese airspace at all — Pope John Paul II had to skirt it in his tours of Asia — is seen as a positive, if small, step forward," Reutersreports.

From Rome, NPR's Sylvia Poggioli reports:

"Traveling popes send routine greetings to heads of states of the countries they fly over. But the message Francis sends to Chinese leaders will be carefully analyzed."During his stay, the pope is not expected to visit the demilitarized zone that separates the two Koreas, but his message of peace and reconciliation will also be aimed at the estimated 200,000 to 400,000 Christians still living in hardship in North Korea."The visit's highlights will be a Asian Catholic youth festival and the beatification of 124 martyrs."South Korea has a vibrant Catholic community, with more than 100,000 people baptized annually. Francis is also expected to meet a group of Korean women the Japanese used as sex slaves during World War II."

There are an estimated 12 million Catholics in China, according to The Wall Street Journal, which notes that many attend underground churches. Those who worship openly do so under the authority of a state-run group of bishops, separate from the Vatican.

"The Holy See has long been anxious to settle relations in China," the Journal reports. "In a conciliatory, 55-page open letter to Chinese Catholics in 2007, Pope Benedict XVI emphasized that the church had no political ambitions."

Copyright 2016 NPR. To see more, visit http://www.npr.org/.