A few Chinese Catholics came to sneak a peek at Pope Francis during an official welcome ceremony in the main square of Mongolia's capital Ulaanbaatar on Saturday, enthusiastically waving their country's flag.

The Vatican does not have diplomatic relations with China, instead recognizing Chinese-claimed Taiwan, while China's Catholics have long been split between a state-backed official church and an underground flock loyal to the pope.

Brandishing red, five-starred Chinese flags, two dozen Chinese nationals who identified themselves as Catholic devotees crowded around a police barrier to catch a glimpse of Francis on Saturday morning.

Yang Guang, a 37-year-old Catholic from Shanghai, said he came to Mongolia for a holiday but was glad to catch a glimpse of the pope at Sukhbaatar Square.

"I'm just extremely happy because this is the first time I've seen him. It's not as if I have this kind of opportunity all the time. I'm just very happy. Passion," Yang told Reuters.

A few other Chinese nationals could be seen receiving blessings from a cardinal on the sidelines of ceremony.

Suzanne Willis, a Christian pilgrim from Hong Kong, said she was moved to tears seeing Francis in person.

"I was just so overwhelmed. I see this very, very nice person that I've admired for a long, long time," said Willis, adding that her group happened upon the ceremony after their flight back to Hong Kong was delayed due to a typhoon.

Mongolia, with its population of about 3.3 million people, is strategically significant for the Roman Catholic Church because of its proximity to China, where the Vatican is trying to improve the situation of Catholics.

Francis, 86, arrived in Mongolia on Friday to visit the country's tiny Catholic community, which at 1,450 members is one of the smallest in the world.

As is customary, Francis, who besides being the leader of the world's 1.3 billion Catholics is also a head of state, wired greetings to the leaders of each country he flew over, including China.

In his message to Chinese President Xi Jinping, Francis said he had good wishes for all the people of China and assured the president of his prayers for the "wellbeing of the nation".

(Reuters)

Pope Francis stands next to Mongolian President Ukhnaagiin Khurelsukh and Khulan Ganbat, 11, while attending a welcoming ceremony at Sukhbaatar Square, during his Apostolic Journey in Ulaanbaatar, Mongolia. (Reuters)

Chinese Catholics sneak a peek at pope in Mongolia