The Russian Orthodox Church enthroned Kirill, seen as an outspoken moderniser, as the leader of its 160-million flock on Sunday, amid hopes he might lead a rapprochement with other Christian Churches.

Hundreds of dignitaries and thousands of ordinary worshippers packed Moscow's huge central Christ the Saviour Cathedral to see Kirill crowned as the 16th Patriarch of Moscow and all Russia since the title was created in 1589.

The 62-year-old new patriarch will oversee the world's second biggest Church, which has grown much stronger, wealthier and more influential in Russia since the collapse of communism.

Most Russians consider themselves Orthodox and the Church may play a key role in moulding the population's response to the economic crisis now gripping the country.

Kirill, a metropolitan (senior archbishop) who formerly headed the Russian Church's external relations department, has previously spoken in favour of more independence from the Kremlin and closer ties with Western Churches.

President Dmitry Medvedev and Prime Minister Vladimir Putin looked on from near the altar, crossing themselves repeatedly as the ceremony proceeded. Grand Duchess Maria Vladimirovna, a descendant of the last Tsar, also attended.

Two metropolitans (senior archbishops) seated Kirill three times in the patriarch's chair at the centre of the altar, chanting "axios" (worthy), along with the clergy and the congregation.

Deacons then replaced Kirill's archbishop's vestments with the deep crimson patriarchal sakkos (tunic), omophorion (bishop's scarf) and mitre.

Priests intoned the deep, sonorous bass tones of the ancient Orthodox liturgy, interspersed with vigorous bursts of praise and thanks for the new patriarch from choirs located on the cathedral's balconies.

Floodlights illuminated the richly gilded interior of the cathedral, itself a symbol of the Orthodox Church's revival. Stalin ordered the temple to be blown up in the 1930s as part of his war on religion but it was rebuilt in the 1990s.

Emissaries from different branches of the Orthodox church, the Vatican and other religions crowded the cathedral, along with ambassadors, government figures and ordinary worshippers.