Zlatan Ibrahimovic believes it is "already written" Lionel Messi will win the World Cup with Argentina and thinks the full truth about Cristiano Ronaldo's Manchester United exit will never come to light.

Messi has been influential in Argentina's run to the semi-finals in Qatar where La Albiceleste will face Croatia on Tuesday.

Should Messi lift the most prestigious international trophy of all with his country, it will further enhance claims the Argentina legend is the greatest to have played the game.

Milan veteran Ibrahimovic, a former team-mate of Messi's at Barcelona, thinks this is the year the Paris Saint-Germain star will get his hands on the prize.

"I think it's already written who will win, and you know who I mean," Ibrahimovic said.

"I think Messi will lift the trophy, it's already written."

Cristiano Ronaldo, a long-term rival of Messi's in the greatest of all-time debate, saw his own hopes of World Cup glory dashed by Portugal's surprise quarter-final defeat to Morocco.

It marked the latest blow in a tough period for the legendary forward, who left Manchester United by mutual consent in the wake of an incendiary TalkTV interview with Piers Morgan in which he criticized the club's hierarchy and boss Erik ten Hag.

Former United striker Ibrahimovic says with all sides defending themselves the actual events of what occurred will never be known.

"His exiting United, I think when things happen, we will never know the true story," he added.

"They say what they want to say, he says what he needs to say to protect himself, then you have the coach that says these things to protect himself. 

"Then the club says things – not like me, I will tell you how it really happened. But we are all different. Everybody is careful about their image. 

"For me, the perfect image is being yourself. The true story we will not know my friend."