The Vatican's top cleric in the heart of Muslim Arabia tends to a flock of 2 million Christians spread around six desert nations. But he has to do it quietly: Most of them must still pray in secret and are forbidden to display crosses and other symbols of their faith.

From his base in the emirate of Abu Dhabi on the Persian Gulf, Archbishop Paul Hinder travels the Arabian Peninsula, even slipping in and out of Saudi Arabia _ the birthplace of Islam, where restrictions on Christians are the toughest.

"We are tolerated, but not popular here," Hinder said in an interview in the archbishop's living quarters inside a Christian compound in Abu Dhabi, the capital of the United Arab Emirates.

He spoke wearing the traditional hooded robe of his Capuchin order. The white garb blends in just fine with the Arab robes worn by men in the region, so he wears it in public _ but without a cross around his neck or the belt of three knots that also mark the order.

"People here know who I am, although I never wear a cross when I go outside out of respect for local conditions," said Hinter, a Swiss citizen.

Still, he says, there are signs of slow change, even in Saudi Arabia, where small groups who in the past would have been punished or deported if caught practicing the Christian services are now left in peace to pray privately.

The UAE and the neighboring Gulf nations of Kuwait, Qatar, Bahrain and Oman have taken greater steps. They have allowed churches to be built on land donated by the countries' rulers, though there are no outward signs that the buildings are houses of worship.

On Thursday night, Hinder led a midnight Christmas Eve Mass for several thousand the faithful at St. Joseph's Cathedral in Abu Dhabi. Reflecting the diversity of the community, more than a dozen Christmas Day services will be held for 10,000 worshippers in at least eight different languages.

The cathedral is in a downtown compound that's also home to Anglican, Greek Orthodox and Egyptian Coptic churches. Crucifixes, icons, rosaries and other religious symbols are allowed within the walled compound. But the buildings' exteriors are spare and flat-roofed, avoiding any church-like architecture.

Besides Saudi Arabia, Hinder also oversees the needs of Catholics in Bahrain, the United Arab Emirates, Oman, Yemen, and Qatar. The vast majority of the region's Christians are migrants from the Philippines, India and other Asian nations, many of whom work as maids, civil servants or in lower management positions at banks and businesses.