Johnson would consider preventing his players from travelling to Oslo
Bristol City could be on a collision course with the Scottish Football Association over the scheduling of the World Cup qualifier with Norway.
City's Paul Hartley, David Clarkson and Jamie McAllister have been named in the squad for the game on 12 August.
"We're going to have to decide whether we allow our players to go," manager Gary Johnson told BBC Radio Bristol.
"Many of the Scottish team are playing in the Championship so I can't work out why they'd have this game now."
The game in Oslo is scheduled to take place four days after the beginning of the new Championship season and just 24 hours after City are due to take on Brentford in the first round of the Carling Cup.
"It's not an international week so I don't think you have to let them go, but it's a qualifying game for Scotland so that makes it a bit difficult," said Johnson.
"Wales have decided to call their players in, so it would be difficult for instance to allow Lewin Nyatanga, who's in our first team, to go for a friendly."
"I'll wait and see who's in the squads and take it from there," he added.
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