Calvert-Lewin missed the start of the season with a knee injury but has appeared as a substitute in Everton's last two Premier League games.
Qatar 2022 is barely a month away and players are making last-minute efforts to get into the thinking of their national team managers.
Calvert-Lewin has won 11 caps for England and scored four goals, and was part of the Three Lions squad at last summer's European championships.
The 25-year-old might be behind his competitors in the race to serve as Harry Kane's back up at the World Cup due to his fitness but Lampard is not discounting his chances of making a late push to be included in Gareth Southgate's travelling party.
"We've got to be careful with Dominic coming back, making sure we gradually bring him in but as quickly as possible," he told reporters ahead of Everton's trip to Newcastle United.
"We're definitely getting to the stage now where we can hopefully get more minutes out of him.
"It's human nature and a natural mentality of top-level players, they want to play for their countries. The first thing is you play well for your club to get there.
"Because of Dominic's injuries it's put him in this position. My feeling is if he'd been fit and playing regularly he'd be making that case.
"It's step by step for us, Dominic is an England player, he's been in that squad – can we get him fit for us first, see what he can deliver for us, then of course he gets himself into that question."
Calvert-Lewin missed a chunk of last season through a series of muscle injuries and only made 17 appearances in the top flight.
He returned for the pivotal run-in matches to help preserve Everton's top flight status with a crucial goal against Crystal Palace.
