Despite the simmering relations between the Vatican and Beijing, China allowed Pope Francis to fly across the country when he made his way to South Korea.

In the past China disallowed popes from flying in its airspace.

As part of a papal custom whenever he flies cver a country, Francis sent a greeting to President Xi Jinping, ucannews.com reported.

"Upon entering Chinese air space, I extend best wishes to your excellency and your fellow citizens, and I invoke the divine blessings of peace and well-being upon the nation," Francis said in the message, which was radioed to Xi.

The government allowed the papal flight to pass Inner Mongolia and Beijing as it made way to Seoul for the Asian Youth Day on Thursday.

The flight crossed 10 different countries and skirted North Korea, which fired rockets shortly before the Pope landed in Seoul.

Pope Francis sent a rare public greeting to President Xi Jinping during the first ever papal flight across China en route to his landmark visit to South Korea.

China is pursuing what observers say is the most severe crackdown on Christianity in recent years.

Houses of worship, as well as religious symbols, have been targeted by in the quest in different part of the country.

Chinese authorities also pilgrimages to Seoul for the pope's five-day visit.

The Holy See and Beijing remain to be odds as disagreements on a host of issues that continue to strain relations.

The Vatican does not recognize the priests the Chinese government ordains and promotes as church officials, in the same manner as the Holy See does not accept controls imposed by authorities in Beijing.

But Francis continued to be upbeat about the relations with China, with representatives from both sides purportedly meeting in June.

In an interview with the Italian press, the Pope shared his thoughts about Xi and China.

"There are relations," he said. "The Chinese are a great people whom I care about."