Amnesty say Ronaldo's signing is part of a "wider pattern of sportswashing".

The Portuguese striker called Saudi Arabia an "amazing country" as he was unveiled by Al Nassr on Tuesday.

Saudi Arabia has invested heavily in sporting events, backing the breakaway LIV Golf series, hosting world title boxing fights and a Formula One grand prix, while the country's Public Investment Fund backed a takeover of Premier League club Newcastle United in 2021.

However, Saudi Arabia has also been accused of human rights abuses and women's rights campaigners have been imprisoned, despite some reform under crown prince Mohammed bin Salman, such as an end to the ban on women driving.

Western intelligence agencies believe the crown prince ordered the murder of journalist Jamal Khashoggi in 2018 - which he denies.

"Instead of offering uncritical praise of Saudi Arabia, Ronaldo should use his considerable public platform to draw attention to human rights issues in the country," Dana Ahmed, Amnesty's Middle East researcher, said.

"Saudi Arabia regularly executes people for crimes including murder, rape and drug smuggling. On a single day last year, 81 people were put to death, many of whom were tried in grossly unfair trials.

"The authorities are also continuing their crackdown on freedom of expression and association, with heavy prison sentences handed down to human rights defenders, women's rights activists and other political activists.

"Cristiano Ronaldo should not allow his fame and celebrity status to become a tool of Saudi's sportswashing. He should use his time at Al Nassr to speak out about the myriad of human rights issues in the country."