Cardinal Walter Kasper, who heads the Vatican's office for relations with other Christian confessions, said both Benedict and Aleksy were open to the meeting.
Kasper said, however, that much depends on the "internal situation" in the Russian Orthodox Church.
Many Russian Orthodox traditionalists oppose a meeting between the patriarch and the pope. The Russian church has accused Roman Catholics of seeking converts in traditionally Russian Orthodox areas, a charge the Vatican denies.
RFE/RL Russia Report
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