Mount limped out of Tuesday’s 4-4 Champions League draw with Ajax due to an ankle injury, while Barkley has a similar issue and has not featured since October 19.
“Ross has got an ongoing issue so he’s not in the squad tomorrow,” said Lampard, whose side host Palace in a lunchtime kick-off at Stamford Bridge on Saturday.
“It’s a conversation that I will have with Gareth (Southgate) or (England coach) Steve (Holland) with Ross to see how it pans out for him over the next 10 days. I’m not sure on that one.
“With Mason, he’s in the squad. We’re giving him another 24 hours and we’ll make a call on that one in the morning.”
Chelsea had five players called up by Southgate, with Fikayo Tomori, Callum Hudson-Odoi and Tammy Abraham joining Barkley and Mount.
Lampard is “proud” to see his youngsters receiving international recognition following fine starts to the campaign.
“Those young boys, I’m pleased that their form and their dedication has got them those call-ups,” said Lampard.
“I know they’re proud, I’m proud as a manager to have them in the England squad.
“I’m proud of all of the players who go away with international teams. But to see young lads getting their first steps into the team is obviously great.”
Lampard has also been singled out for praise and earlier on Friday was named Premier League manager of the month for October.
The former Derby boss guided Chelsea to three successive league victories last month as part of a seven-match winning run in all competitions.
He took the opportunity to pay tribute to the club’s staff and hopes his team’s forthcoming results and performances are not adversely affected by a curse which is purported to follow the accolade.
“It doesn’t confirm to me that I am doing a good job. Albeit it is a nice award to get on an individual basis,” said Lampard.
“It certainly is an award that relates to much more than that, about what the club is doing and the people working behind the scenes. I appreciate it and I receive it not just for myself.
“On the curse, I have heard of it. I know it and I am relatively superstitious. I was always as a player and I carry it into my management.
“So hopefully the players will go out and prove the curse wrong tomorrow because we want to carry on our momentum.”
Lampard also confirmed defender Antonio Rudiger, who has made only one appearance this season, underwent surgery on a groin problem this week and could return to contention in three weeks.
“It was nice to get something definitive about it,” said Lampard. “We’ve been trying to find a solution, Toni’s been having some issues, it’s not easy for a player in that position, so hopefully we are at that case now and in three weeks we’re in a better place.”
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