France beat Uruguay 2-0 in Nizhny Novgorod on Friday to reach the semi-finals where they will face Belgium in St. Petersburg on Tuesday.

Belgium beat five-time champions Brazil 2-1 in Kazan to reach the last four.

"I don't think the match against Brazil was the hardest. All World Cup matches are hard. Individually, the French players have the same qualities as Brazil. If you lose concentration for a moment, they will attack. We can't go on the pitch [tomorrow] and believe that the hardest part is over," Martinez told journalists.

The 2018 FIFA World Cup kicked off on June 14 and will continue until July 15, with the final set to be played at Moscow's Luzhniki Stadium.