The Bees stopper has been in impressive form so far this season and, given the amount of English goalkeepers in the top two divisions, must be an option in the event of an injury to one of the squad.
And Smith believes that the Three Lions will be fully aware of how the 23-year-old is doing.
He said: “I'm sure they'll keep tabs on him. I'm not sure how their selection system works but they'll be aware of him. He just has to focus on playing at Championship level.”
Smith believes that Bentley could be lining up at Wembley representing his country one day, as long as he continues to play in the way he has done this season.
He added: “With what I see every day in training and with his work ethic, he can go all the way.
“There aren't many English goalkeepers around and I believe he's that good. We need to be patient and not rush it.
“He's been in League Two, League One and now the Championship. He's had a good time – there'll be times when he'll need support but he's learning at a better level now and, with that, I believe he'll get better.”