Pope Benedict XVI is joining Twitter promising "pearls of wisdom" in eight languages under the handle @pontifex, the Vatican announced on Monday.

Papally-approved tweets will begin next week just in time for Christmas celebrations, as the Catholic Church tries to reach a wider audience and harness social media to woo the Internet generation.

"The first tweets will be answers to questions sent to the pope on matters of faith. The public can start sending them now," Greg Burke, a senior communications adviser to the Vatican, told a packed press conference.

The account carries a picture of the pope waving and its followers rose from around 2,400 at the time of the announcement to more than 24,000 just an hour later -- still only a tiny fraction of the world's 1.1 billion Catholics.

An introductory message on the account based in "Vatican City" read: "Welcome to the official Twitter page of His Holiness Pope Benedict XVI."

"Pontifex" is a Latin word meaning "pontiff", the pope's official title.

Benedict will only follow his own account in other languages for the moment and there are no plans for a Facebook account yet, Burke said, adding: "Twitter can be more effective than Facebook in passing on the Pope's message."

The tweets will be in Arabic, English, French, German, Italian, Polish, Portuguese and Spanish and more languages could be added in future.

Several fake Twitter accounts already set up in the pope's name have been used to mock the 85-year-old pontiff, but the Vatican said it was not worried about the risk that hostile messages would be tweeted on the real account.

Burke, a former correspondent for US channel Fox News brought in by the Vatican in June to overhaul its public-relations operation, said the pope's Twitter account would create "a free market of ideas, and that is good".

It would serve up "pearls of wisdom coming from the heart of the pope", he said, though the 140-character messages will not be written by the pope himself but by Vatican officials who will then submit them to him for approval.

"We are going to get a spiritual message. The pope is not going to be walking around with a Blackberry or an iPad and no one is going to be putting words into the pope's mouth. He will tweet what he wants to tweet," Burke said.

The Vatican said: "The pope's presence on Twitter is a concrete expression of his conviction that the Church must be present in the digital arena."

Benedict wants "to ensure that the good news of Jesus Christ and the teaching of his Church is permeating the forum of exchange and dialogue."

The aim is to "dialogue with men and women of today wherever they are," said Cardinal Claudio Maria Celli of the Pontifical Social Communications Council.

Celli said the papal tweets would be like "sparks of truth".

The news of the elderly pontiff's decision to join Twitter received mixed reactions on the online community.

"Does this mean we can just tweet our sins instead of showing up for confession?" asked Twitter user Sandra Hayes.

Several leading Vatican prelates are already regular tweeters including Cardinal Gianfranco Ravasi, head of the Pontifical Council for Culture, as the tradition-bound institution tries to reach a younger global audience.

Brazilian Cardinal Odilo Scherer, American Sean Patrick O'Malley, Italian Angelo Scola and South African Wilfrid Fox Napier also tweet -- out of 200-plus cardinals in the world, many of whom might not be quite as tech-savvy.

Father Antonio Spadaro, director of the Jesuit journal Civilta Cattolica and one of the Church's Twitter pioneers, said the pope's decision was comparable to the first radio broadcast by pope Pius XI on February 12, 1931.

"Social media are real places of emotion where people share their lives, their best and worst desires, their questions and their answers," he said.

Benedict last year launched a new Vatican information portal with a tweet from the Holy See's Twitter account sent from an iPad. A bemused pope could be seen in images of the event being shown by prelates how to tap on the device.

"Praised be our Lord Jesus Christ! With my prayers and blessing, Benedictus XVI," read his first tweet, which he signed with his formal Latin name.