(REUTERS) — The end of communist rule in Europe, which began 25 years ago this month, was not all positive for Christianity because it brought tensions between Rome and Russia back to the surface, a senior Vatican official said on Monday.

Cardinal Kurt Koch, the top Roman Catholic official for inter-church relations, said the re-emergence of Eastern Catholic churches in Ukraine and Romania after decades of suppression had created major tensions with the Russian Orthodox Church.

Russian Orthodox leaders have accused the Vatican-aligned Ukrainian Greek Catholic Church of trying to take back churches and woo away believers from the Moscow Orthodox Patriarchate. The Ukrainian church and the Vatican deny this.

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