Chadli opts to play for Belgium
Chadli said he had received invitations from both nations and had opted for Belgium, the country of his birth, who play a friendly against Finland in Ghent next Wednesday.
The 21-year-old withdrew from Morocco's squad for next week's friendly against Niger.
"I had a positive discussion with (Belgium coach George) Leekens and decide to play for Belgium," Chadli wrote on his personal website.
The player has dual nationality because his parents hail from the north African kingdom and he is still eligible to play for Belgium because his Morocco debut against Northern Ireland came in a non-competitive match.
He will only be tied to a single country once he plays a competitive international like a European Championship or Africa Cup of Nations qualifier. Belgium and Morocco have competitive games scheduled for late March.