Van Persie played for Netherlands in their 3-2 win over England at Wembley Stadium on Wednesday while Vermaelen featured in Belgium's 1-1 draw with Greece, but Wenger said they went into their games carrying injuries and have deteriorated since.
"We have a problem with Vermaelen that we have to assess today," a clearly irritated Wenger told reporters on Friday at Arsenal's training ground at London Colney, north of London.
"Van Persie has a little groin problem that we have to assess," he added, saying he was unhappy they were called up for Wednesday's friendlies.
"It's difficult to understand that our players had to go injured - it's disrespectful to the players."
Wenger continued: "We played Tottenham on Sunday then they played an international, then we are at Liverpool on Saturday lunchtime, then face AC Milan next Tuesday. Any football player knows it's impossible to play four games at the top level like that.
"Personally I think international friendlies are becoming more difficult to accept."
Both Arsenal and Liverpool are approaching Sunday's game in good spirits following Arsenal's 5-2 comeback win over Spurs last Sunday and Liverpool's penalty shootout win over Cardiff City in the League Cup final at Wembley on the same afternoon.
