The call came as the Catholic church in China ordained another bishop yesterday without the Pope's approval - the third in eight months.

This was denounced by Cardinal Zen, who questioned whether Patriotic Association officials were really behind the ordinations.

Cardinal Zen took out a half-page advertisement in the Hong Kong newspaper - the Apple Daily - on Wednesday to issue an "urgent appeal" to President Hu Jintao and Premier Wen Jiabao. He called on the two leaders to restrain what he called "rogue public servants" who are "using violence to assist scum inside the church to force bishops, priests, and followers to do things against their consciences."

The latest ordination has deepened a standoff in which the Vatican insists the pope has the sole right to appoint bishops, but Beijing leaders see that position as foreign interference in their internal affairs.