Catholic pilgrims cried out as the first smoke to appear from the Sistine Chapel chimney turned black on Tuesday -- meaning no pope had been elected -- saying they hoped for a strong leader who could lead the Church in troubled times.

"I'm a bit disappointed, I was really hoping this was the one. But I'll be back tomorrow morning early!" said Kenneth Brown, one of tens of thousands in the crowd who travelled from London hoping to be present for the election of a pope.

But Father Joseph, a 36-year-old priest from Sydney, said: "It makes it even more exciting! The black smoke pouring out like that, it was like something out of Lord of the Rings!"

"It was brilliant, what a great experience. It's increased our anticipation. I know the Holy Spirit will choose a new pontiff for us soon," he added with a grin.

The priests, nuns and families gathered in the square in the rain let out a collective gasp as the smoke emerged, signalling the 115 cardinal electors had cast their first vote -- but without a two-thirds majority.

The sense of anticipation had not been dampened by heavy bursts of rain, and the faithful said they would now increase their prayers for a guide who could breathe new life into the Church.

"Ever since Benedict XVI resigned I've been waiting for this moment, I'm so excited," said Paula Murphy from Ireland, who had travelled to Rome with her parish.

"It's a moment for renewal, for a newly united Church," the 38-year old said as she stamped her feet to keep warm.

French priest Guillaume Le Floch said: "Without a pope I feel bereft, like an orphan. I pray to give the cardinals the strength to choose the right man to lead the Church."

"It cannot be an easy decision, but the Church needs a great leader now more than ever. The cardinals have a chance to astonish us," the 35-year-old said.

Despite the cold, pilgrims had taken up position all afternoon under the balustrades surrounding the square, determined to get a front row seat of the chimney.

As night fell and spotlights lit up the front of St. Peter's Basilica, many were praying for white smoke, indicating a new leader for the world's 1.2 billion Catholics had been chosen.

Sister Celestina, 62, a nun from Croatia, said: "We'll be praying for the cardinals until a decision is made."

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

A stone's throw from the Vatican, young Catholics from all over the world were praying in 24-hour vigils.

"We are holding non-stop prayers here, day and night, asking people to come and support the cardinals with their prayers," said Fabien Lambert, chaplain of the 12th-century Saint Lawrence church and international youth centre in Rome.

Pre-conclave talks among cardinals gathered in Rome after Benedict's resignation appeared to focus on the problems afflicting the Curia -- the Vatican's unruly governing body -- and its distance from the grassroots.

"It's a dangerous period. The Church is much more divided now than it has ever been, and it is with trepidation and concern that we wait for the decision as to who is chosen," said Nicholas Gruner, a 70-year-old priest from Montreal.

"If they don't choose the right pope, it could make the situation a lot worse. We may not deserve a good pope as sinners, but we certainly need one."

Saverio, a white-haired 71-year-old Italian architect who took time off work to come to St Peter's Square, said the Church had lost touch with the simple pilgrims.

"The Church's biggest problem is its estrangement from the real world. Priests don't care about others any more, nuns live in their own world," he said.

Others were more positive: Francesca Rivello from Milan said she thought all the cardinals had something special to offer.

"There's an electric feeling in the air. I have a feeling the new pope is going to be a great one," the 27-year-old said.