The Vatican is studying calls from cardinals to hold a papal conclave earlier than planned, after Pope Benedict XVI steps down on 28 February.

Under current rules, the election can be held on 15 March at the earliest, to allow cardinals enough time to travel to Rome.

Vatican spokesman Federico Lombardi said officials were examining if a rule change was possible.

Benedict XVI, 85, announced his shock resignation last Monday.

They did not wait long to start the search.