Gerard Lopez's charges will play their first ever FIFA sanctioned match during the current international break when they face Venezuela in a friendly.
Both Pique and Xavi Hernandez are set to be involved after accepting their respective call-ups.
"I'm sure Gerard [Pique] has his reasons for playing with the Catalan national team," Alba explained in his pre-match press conference.
"I've not spoken to him about it, but he decided to leave the national team and now wants to play for Catalonia.
"They have one game a year and he will want to play."