The 20-year-old striker has struggled for game time at Elland Road this season.
"Now is not the moment, we are in October," said the Spaniard. "He is in Leeds and I respect the coach and his decision.
"Firstly I respect his coach (Marcelo Bielsa) and his decision. I think he is going to play more. He is going to deserve it.
"Each match he plays with Leeds and the national team is important for him and important for Arsenal also because we want him to get confidence and take experience and use it in the future for us.
"He is doing it. He is maybe playing less than we want, but I am sure he will play more."