Will the arrival of a new Pope clash with the enthronement of the new Archbishop of Canterbury on March 21? The mere possibility has caused real anxiety among Church officials. If Pope Benedict does not issue a Motu Proprio bringing forward the date – he is still expected to – the conclave will not begin until March 15. The nightmare scenario, then, is that the conclave ends – and the world watches as a new Pontiff emerges on the balcony of St Peter’s – on the day of Archbishop Welby’s installation. The story would push the Anglican celebration way off the global news agenda.

The cheerier news, for ecumenists at least, is that, if things turn out well, a newly ensconced Archbishop Welby might join the new Pope’s inauguration Mass on Palm Sunday.

Still, the possible collision is a real headache. Anglicans can’t expect the Vatican to pay any attention to their schedule. The Roman Catholic Church gave the world the Gregorian calender, remember – so it understandably feels somewhat proprietorial when it comes to times and dates. In 2005, Prince Charles and Camilla had to postpone their wedding to attend John Paul II’s funeral. What will Welby do if his big day is similarly overshadowed by the bigger party in Rome?

Tags: Pope Benedict XVI, Vatican