Cristiano Ronaldo completes Al Nassr move

Portugal captain Cristiano Ronaldo has joined Saudi Arabian club Al Nassr on a two-and-a-half year contract, weeks after leaving Manchester United as a free agent.

Ronaldo departed Old Trafford last month following an explosive television interview in which the 37-year-old forward said he felt betrayed by the club and did not respect their Dutch manager Erik ten Hag.

Al Nassr issued a statement on Friday saying the five-time Ballon D'or winner will join on a deal until 2025 but did not disclose any financial details.

Ronaldo's contract has been estimated by media to be worth more than 200 million euros ($A315m).

"I am fortunate that I have won everything I set out to win in European football and feel now that this is the right moment to share my experience in Asia," Ronaldo said in a statement.

"I am looking forward to joining my new teammates and together with them help the club to achieve success."

Ronaldo will arrive in Saudi Arabia with a vast collection of club honours after a glittering spell at Spanish giants Real Madrid from 2009-18 where he won two La Liga titles, two Spanish Cups, four Champions Leagues and three Club World Cups.

He scored a club record 451 times for Real and has more than 800 senior goals overall for club and country.

Ronaldo claimed two Serie A titles and a Copa Italia trophy in three years at Juventus before rejoining United - with whom he had previously won three Premier League crowns, the FA Cup, two League Cups, the Champions League and the Club World Cup.

He played for Portugal in Qatar, where he became the first player to score in five World Cups after netting a penalty in his side's opening Group H game against Ghana.

Portugal were knocked out in the quarter-finals by Morocco.

Ronaldo said Qatar would probably be his last World Cup as he plans to retire at 40, with a move to Saudi Arabia likely to mark the swansong in the career one of the game's greatest current players alongside Lionel Messi.

"This is more than history in the making," Al Nassr president Musalli Almuammar said.

"This is a signing that will not only inspire our club to achieve even greater success but inspire our league, our nation and future generations."

The Saudi Arabian club, who have won nine Saudi Pro Premier League titles, are hoping Ronaldo can help them to a first AFC Asian Champions League success.

However, the Portuguese forward will miss his first two domestic games after being banned for knocking a phone out of a fan's hand after United's defeat at Everton in April.