By Philip Pullella
VATICAN CITY, May 22 (Reuters) - Pope Francis paid tribute on Wednesday to Chinese Catholics for holding on to their faith despite "hardships and trials", an apparent reference to Beijing's restrictions on religion.
His comments to tens of thousands of people gathered in St. Peter's Square for his weekly general audience came as the Vatican and China are still in the implementation phase of a landmark deal, signed last September, on the appointment of bishops.
The deal has split Catholics in China and around the world, with some critics of the pope saying he has caved in to the Communist government. The deal's most outspoken critic has been Cardinal Joseph Zen, the former archbishop of Hong Kong.
Francis noted that this Friday would mark a feast day particularly celebrated by Catholics at the shrine of Our Lady of Sheshan, near Shanghai.
"This happy occasion allows me to express special closeness and affection to all the Catholics in China, who, among daily hardships and trials, continue to believe, to hope and to love," he said.
Francis also urged Catholics in China to "always remain united in communion with the universal Church".
China's constitution guarantees religious freedom, but since President Xi Jinping took office six years ago, the government has tightened restrictions on religions seen as a challenge to the authority of the ruling Communist Party.
The government has cracked down on underground churches, both Protestant and Catholic, even as it seeks to improve relations with the Vatican.
China has been following a policy it calls the "Sinicisation" of religion, trying to root out foreign influences and enforce obedience to the Communist Party.
Restrictions on religion in China have attracted particular concern in the United States. In March, during a visit to Hong Kong, the U.S. ambassador for religious freedom called on Beijing to end religious persecution.
Also in March, a senior Chinese official accused Western forces of trying to use Christianity to influence China's society and even "subvert" the government, warning that Chinese Christians needed to follow a Chinese model of the religion. .
The pope has defended the Vatican deal with China on the appointment of bishops, saying he, and not the Beijing government, will have the final say on who is named.
China’s approximately 12 million Catholics have been split between an underground church swearing loyalty to the Vatican and the state-supervised Catholic Patriotic Association.
The Vatican has said the absence of a deal could have led to a schism between Chinese Catholics that would have been difficult to heal.
(Additional reporting by Ben Blanchard in Beijing; Editing by Gareth Jones)