Newcastle United head coach Eddie Howe insists Alexander Isak has "to earn the right to train with us" following recent media reports about his future at the club.
Isak has been the subject of transfer speculation this summer. Premier League champions Liverpool have been linked with the forward, who scored 23 goals for Newcastle last season.
The 25-year-old returned to Newcastle on Monday, having spent time training separately at his former club Real Sociedad.
"You have to earn the right to train with us," said Howe.
"He's like any other player, we would expect him to come in and train as normal."
'You have to act in the right way'
Isak, who scored the winner against Liverpool in last season's EFL Cup final, to help Newcastle end their 70-year wait for domestic silverware, missed the Magpies' pre-season trip to South Korea.
"We are Newcastle United," Howe continued. "The player has a responsibility here to be part of a team and part of a squad - you have to act in the right way. So that is also at play here.
"We will make sure that any player does that, to earn the right to train with the group. No player can expect to act poorly and then train with the group as normal."
Newcastle kick off their Premier League campaign at Aston Villa on Saturday 16 August.