Cardinals today moved into the Vatican as the suspense mounted ahead of a secret papal election with no clear frontrunner to steer the Catholic world through troubled waters after Benedict XVI’s historic resignation.

The 115 cardinal electors who pick the next leader of 1.2 billion Catholics in a conclave in the Sistine Chapel will live inside the Vatican walls completely cut off from the outside world until they have made their choice.

In a series of centuries-old rituals today, cardinals will be sworn in with a solemn oath that threatens anyone who reveals the deliberations of the conclave with instant excommunication.

Dozens of Vatican staff working on the conclave, including cooks, drivers and security guards, yesterday swore the oath and jamming devices have been installed to prevent any bugging or communication in or out of the chapel.

The prayers will begin with a special mass called 'For the Election of the Roman Pontiff' in St Peter’s Basilica starting at 0900 GMT.

Cardinals will later file into the Sistine Chapel from 1530 GMT chanting in procession to invoke the Holy Spirit to inspire their choice.

The cardinals are set to hold a first round of voting later today — but the Vatican has already said it expects the smoke from the burning of the ballots to be black indicating no papal election has taken place.

Ballots on subsequent days will be burnt at around 1100 GMT after two rounds of voting in the morning and at around 1800 GMT after two rounds in the afternoon — the smoke is famously turned white if there is a new pope.

Catholics around the globe have been praying for the conclave, which is expected to last no more than a few days.

“We’ll be praying for the cardinals until a decision is made, it’s the part we play in the conclave,” said sister Celestina, 62, a nun from Croatia, kneeling in a church near the Vatican.

“The Church is like a boat, all the faithful are sailing in it together but we’re without a helmsman at the moment.”

Among the possible candidates, three have emerged as favourites — Italy’s Angelo Scola, Brazil’s Odilo Scherer and Canada’s Marc Ouellet, all of them conservatives cast in the same mould as “pope emeritus” Benedict XVI.

But the rumour mill in the Vatican has thrown up more names too including cardinals from Austria, Hungary, Mexico, the Philippines, South Africa and the US — many of them inspiring pastoral figures in their communities.

The field is wide open although a few key aims unite many of the cardinals after Benedict’s rocky eight-year papacy — reform the intrigue-filled Vatican bureaucracy, counter rising secularism in the West and find new inspiration for Catholics in the way John Paul II did.

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