RIYADH, Saudi Arabia (AFP)— Portuguese star Cristiano Ronaldo pledged to remain in Saudi Arabia next season on Thursday despite failing to land any silverware since his lucrative move to the oil-rich kingdom.

Ronaldo's January signing for Al Nassr has been followed by speculation about how long he will stay, including reports of a swap deal with Saudi-owned Newcastle United who have now qualified for next season's Champions League.

But the 38-year-old said in an official Saudi Pro League interview: "I am happy here, I want to continue here, I will continue here.

"And in my opinion if they continue to do the work that they want to do here, for the next five years, I think the Saudi league can be a top five league in the world."

Ronaldo's 14 goals in 16 league appearances were only enough for a second-place finish for the Riyadh club, a favourite of some senior Saudi royals.

In January, the former Manchester United, Real Madrid and Juventus marksman signed a two-and-a-half year deal said to be worth more than 400 million euros.

He admitted some Saudi conventions had taken him by surprise, including late-night training sessions during the fasting month of Ramadan.

"In Europe we train more in the morning, but here we train in the afternoon, or evening and in Ramadan we train at 10 at night," he said.

"So this is so strange, but as I tell you these situations are part of an experience, memories. I like to live these moments because you learn with these things."

He added: "I expected to win something this year, but we didn't, but next year I am really positive and confident that things will change, and we go in a better way."