The Spaniard will feature in all 21 races for McLaren this season, as
well as driving for Toyota at five endurance events including the 24
Hours of Le Mans.
But Perez feels Alonso has ultimately bitten off more than he can
chew because it will be too difficult to give 100 per cent commitment to
two full seasons.
That's a really hectic programme," Perez told El Mundo Deportivo.
"With how busy we are, not only with races but also the simulator and
everything else that we have to do, I think it's impossible to do.
"You would have to find the perfect compromise with your calendar to
achieve it, but I don't think you can do two seasons at once.
"Right now we have 21 races which requires a lot of commitment, so at this point in my career I would not consider it."