Two-time World Cup winner Ronaldo has announced he will retire from professional football at the end of next year.The Brazilian, regarded as one of the best footballers ever, has spent most of his career in Europe but will end it with Corinthians in his homeland."I've already made up my mind - these will be my last two," said the striker.Ronaldo, 33, has scored 62 goals in 97 appearances for Brazil and hopes to be in squad for this summer's World Cup.The striker, who is the all-time leading World Cup finals scorer with 15 goals, said there was "still a possibility" of a call-up for the South Africa tournament - despite not playing for Brazil, which will host the 2014 competition, since 2006."But for 2014 it's impossible - time goes by for everyone," he added.Ronaldo extended his contract with Corinthians on Monday and said of his remaining time at the club: "I'll give my best and I'm hoping to have some fun and win many significant titles."It will bring an end to his 17-year-career, during which time the Brazilian formed part of the World Cup winning teams of 1994 and 2002.The striker also played in the 1998 World Cup final, when Brazil were beaten by France.The match became famous as Ronaldo's name was mysteriously missing from the team sheet, but reappeared shortly before the kick-off and he gave an under-par performance.It subsequently emerged that he had suffered a convulsion but had been cleared to play in the match in Paris.The striker, who began his career with Cruzeiro in his home country, won the Fifa Player of the Year and the Ballon D'or awards in 1997 and 2002, also being handed the former prize in 1996.He moved to PSV Eindhoven while still a teenager, scoring 42 goals in 45 matches.The striker soon came to the attention of Sir Bobby Robson's Barcelona, whom he joined in 1996, scoring 34 goals in 37 league matches.But he only stayed at the Nou Camp for a season, switching to Inter Milan for a then-record fee of £18m, helping the Italian side win the Uefa Cup during his five years with the club.However, it was at Inter that he suffered the first of a series of debilitating knee injuries that would affect the rest of his career.His next club was Real Madrid, who won the Primera Division crown during his first season at the Bernabeu.He returned to Italy in 2007 with AC Milan but made 20 only league appearances, before later joining Corinthians.As to his future after he hangs up his boots, Ronaldo's agent Fabiano Farah said: "Ronaldo will become a representative of Corinthians abroad."We will combine his name and the importance it has with the strength of the club."Source: BBC