Pope Benedict has changed Catholic Church rules to allow the conclave that will choose his successor to be held earlier if cardinals are ready, the Vatican said Monday.

In a motu proprio – in effect, a personal decree – he introduced modifications to the laws governing the timing of the secret election, which had been due to begin on March 15 or later.

Pope Benedict XVI officially stands down from his role on Feb 28, having resigned earlier this month citing his own failing health.

A conclave – the behind-closed-doors ballot of cardinals – cannot begin within 15 days of the papacy becoming vacant; in this case, March 15.

But the amendment to that rule, announced on Monday and reported by Vatican Radio, means the process could begin earlier if all the eligible cardinals arrive in Rome sooner.

Slideshow: The life of Pope Benedict XVI

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Joseph Ratzinger became Pope Benedict XVI in 2005. Look back at his life from childhood through his papacy.

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The date of the conclave's start is important, The Associated Press reported, because Holy Week begins March 24, with Easter Sunday March 31. In order to have a new pope in place for the church's most solemn liturgical period, he would need to be installed by Sunday, March 17 — a tight timeframe if a conclave were to start March 15.

The number of cardinals eligible to take part reduced by one, from 117 to 116, on Monday after the sudden departure of Britain’s most senior Roman Catholic, Cardinal Keith O’Brien, who is facing allegations from priests of “inappropriate behavior.”

The Observer newspaper reported Sunday that the Vatican had been notified of the allegations, which stretch back 30 years.

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