A senior cleric from the Russian Orthodox Church has had a rare meeting with Pope Benedict XVI at the Vatican - seen as a step towards reconciliation.
Pope Benedict XVI is promoting Christian unity
The Vatican described as private the meeting between the Pope and the head of foreign relations of the Moscow Patriarchate, Metropolitan Kirill.
Relations between the two churches have been strained for several years.
Moscow accused the Roman Catholic Church of trying to convert Orthodox faithful in Russia and other countries.
It also rejected repeated requests by the late Pope John Paul II to visit Russia.
But Russian Patriarch Alexy II called for co-operation between the two churches after the election of Pope Benedict last year.
Pope Benedict has made the promotion of Christian unity one of the main goals of his pontificate.
Metropolitan Kirill, who met the Pope last year, was to consecrate the first Orthodox church being built in Rome during his visit to Italy.