The deal that saw the 37-year-old join the Saudi Arabian club was announced on Friday.
Ronaldo will receive $175million annually for the duration of his two-year contract.
“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.
“I am looking forward to joining my new teammates and together with them help the Club to achieve success,” Ronaldo said.
The five-time Ballon d’Or winner was believed to be keen on continuing his career at the top level in Europe.
Ronaldo was especially keen to join a Champions League side after his contract at Manchester United was terminated in November.