
The RBFA did not disclose the nature of the injuries, but Liverpool said Mignolet was expected to be available for the Premier League game away to Tottenham Hotspur on September 15.
Fellaini had been called up by Belgium coach Roberto Martinez on the back of his first start for Manchester United in their 2-0 league victory at Burnley last weekend.
Benteke has started all four Premier League games for Crystal Palace this season but has yet to score.
The uncapped Davy Roef, on loan at Waasland-Beveren from Anderlecht, has been called up, although fellow goalkeepers Thibaut Courtois, Koen Casteels, and Matz Sels are already in the squad.
Belgium face Scotland in a friendly at Glasgow’s Hampden Park on Friday and Iceland in a Nations League match at the Laugardalsvöllur stadium in Reykjavik on Tuesday.