'The Pope called yesterday for unity between the Roman Catholic and Orthodox churches before the end of the millennium, seeking an end to nearly ten centuries of division.

'In an encyclical that took both his own and the Orthodox churches by surprise, the Pope said 'full unity in legitimate diversity' was his purpose. 'On the threshold of the third millennium, we are seeking the re-establishment of full communion.'

'The Catholic Church, while recognizing the baptisms of other mainstream churches and the ministerial orders of the Orthodox Church, does not admit members of any other church to Holy Communion. To admit the Orthodox would be an unparalleled step forward which could be a precursor to communion with other denominations, such as the Church of England.

'The Pope, writing on the eve of the visit to Rome next month of Patriarch Bartholomew of Constantinople, head of the Greek Orthodox Church, wants to reunite the world's 958 million Catholics with the 200 million Orthodox Christians. Acknowledging the need to develop the papacy, he calls on leaders of other churches and their theologians 'to engage with me' to find new forms of exercising his ministry as Bishop of Rome so that it might be accepted by all. The Pope's underlying agenda is evangelism. He believes that a united church is better fitted for the task than one split by ancient feuds.

'The Catholic Church desires nothing less than full communion between East and West,' he says, admitting the 'grave crises' that have sometimes shaken the Catholic Church, 'the infidelity of some of her ministers, and the faults into which her members daily fall.' He concedes 'many elements of great value' are found in other churches.

'The split between the largely Greek Orthodoxy, a family of autonomous churches that recognizes the Patriarch of Constantinople as its titular head, and the Latin Catholic Church was almost inevitable after the division of the Roman Empire into East and West. The two have been separate since the great schism of 1054.

'The central difference was over the wording of the Nicene Creed, the Church's universal statement of belief formulated in 325 AD. While the Orthodox are willing to regard the Pope as the chief bishop in Christendom, they regard him as 'first among equals' in the worldwide episcopal college and do not allow him universal jurisdiction.

'The Orthodox believe in the bodily assumption of the Virgin Mary but deny her immaculate conception, as taught by the Catholic Church. Many Orthodox take Holy Communion only four or fove times a year, compared with the Catholic practice of weekly Communion.

'The Pope makes clear there can be no question of 'altering the deposit of faith' but says: 'Intolerant polemics and controversies have made incompatible assertions out of what was really the result of two different ways of looking at the same reality' (The Times, London, May 31, 1995).