PARIS -- Lionel Messi joined star-packed Paris St Germain on Tuesday after leaving Barcelona, the club where he had begun and expected to end his career.

Messi, a six-times winner of the Ballon d'Or for Europe's best soccer player, signed a two-year contract with an option for a third year, the club said in a statement on its website.

The move will add the Argentine, one of the best players of his generation, to an already formidable PSG attack that includes Brazil's Neymar and French World Cup winner Kylian Mbappe.

"I am excited to begin a new chapter of my career at Paris Saint-Germain," PSG quoted Messi as saying. "I am determined to help build something special for the club and the fans, and I am looking forward to stepping out onto the pitch at the Parc des Princes."

The arrival of Barcelona's record scorer, with 672 goals, will boost Qatari-owned PSG's ambitions to win the prestigious, and lucrative, European Champions League for the first time.

"He has made no secret of his desire to continue competing at the very highest level and winning trophies, and naturally our ambition as a club is to do the same," PSG president Nasser Al-Khelaifi said.

PSG wasted little time in targeting Messi after the heavily indebted Catalan club made clear it could not afford to keep him because of La Liga's financial fair play rules. 

Crowds of supporters thronged to the club's Parc des Princes stadium, chanting and setting off smoke flares.

"It's going to be mad. There's a legend arriving, after all," said supporter Florent Chauveau.

Messi arrived in Paris on a private jet earlier in the day with his wife and three children, waving to hundreds of supporters gathered outside the airport before being whisked to a private hospital for a medical. He later waved to dozens of fans who had assembled beneath the balcony of his hotel room.

From tears to smiles

Only two days ago, Messi had wept as he bade farewell to his boyhood team, describing his feelings at being told he had to leave as like having "a bucket of cold water poured over me".

However, he said he wanted to carry on competing and that he still harboured ambitions to win another Champions League trophy - one that his new club has never won, despite Qatar Sports Investment's lavish spending.

Neymar and Mbappe were already the two most expensive soccer players in history, and the addition of Messi to Mauricio Pochettino's PSG line-up could rival the unstoppable triumvirate that he formed at Barcelona with Neymar and Luis Suarez.

Messi will wear the number 30 shirt, the club confirmed in a video posted on its Twitter feed, headlined "a new diamond in Paris".

Messi, who won four Champions Leagues and 10 domestic league titles with Barcelona, joins several other big names arriving at PSG on a free transfer this summer.

Spain defender Sergio Ramos was no longer wanted at Real Madrid, Dutch midfielder Georginio Wijnaldum had run down his contract with Liverpool and Italy's Euro 2020-winning goalkeeper Gianluigi Donnarumma also joined after his contract with AC Milan ran out.

The arrival of Messi, whose last contract with Barcelona was worth a total of 555 million euros ($650 million) and reported to be the most lucrative in world sport, is also set to provoke a renewed new debate about UEFA's financial fair play rules.

Soccer's European governing body introduced the rules in 2009 in an attempt to restrict the power of free-spending owners to buy success, but their success is debatable.

The star-power of Messi, who has 245 million followers on Instagram, will be welcome news for Ligue 1 as a battle rages between broadcasters over the price of its television rights, crucial to the finances of the clubs. 

($1 = 0.8532 euros)