The 35-year-old Paris St Germain striker will once again take on Argentina’s hopes in Qatar as they seek the South American country’s third world title and first since 1986.
“When we talk about candidates, we always talk about the same teams,” Messi told the South American Federation Conmebol.
“If I have to put some above others, I think Brazil, France and England are a bit above the rest. But the World Cup is so difficult and so complicated that anything can happen.”
Messi reached the final with Argentina in 2014, but suffered against Germany in extra time.
Copa American champions Argentina have been unbeaten for 35 games and if this is Messi’s last World Cup they will be in shape to clinch the title.
“We’re really looking forward to it. We have a really nice group that’s very eager, but we’re thinking of going little by little,” he said.
“We hope to start the World Cup in the best way to face everything that comes after. The more you play and the more time you spend on the pitch, the better you get to know each other.”
Argentina’s opening match in Group C is against Saudi Arabia before taking on Mexico and Poland.