Millar has been named in the 22-man squad for the Canadian national team's upcoming friendly international against New Zealand which will take place in Spain on Saturday, March 24.
Gerrard feels that Millar deserved his call-up due to his performances for the U-18's and U-23's this season.
"It's a special moment for him and he deserves it," the U18s boss told Liverpoolfc.com.
"He's worked really hard for that opportunity."
Millar is a first-team regular under Gerrard and is likely to captain the U19's when they face off against Manchester United in the UEFA Youth League quarter-finals this afternoon.