Ibrahimovic will leave Paris Saint-Germain on a free transfer when his contract expires at the end of the month and is being tipped to link up with United manager Jose Mourinho, whom he worked with at Inter.
But Hamren, who believes speculation surrounding the 34-year-old's future won't affect his performances for Sweden, insists the striker is not allowed to leave camp midway through the tournament to sign for the Red Devils.
"Players have their leisure time on the schedule, what they do then there's nothing I can do to control. But it would not be okay for Zlatan to fly to Manchester," said Hamren.
"I'm 100 per cent sure it [the speculation] will not affect Zlatan. He has been in the business a long time. He handles it perfectly."
Hamren is also confident that the rest of his players won't be affected by the intense media attention around Ibrahimovic.
He added: "The players of the national team are accustomed to all the rumours surrounding Zlatan too. They are familiar with it. There is absolutely nothing that has affected us negatively in the group.
"I am sure the rumours surrounding the captain will not affect the team. I understand there is a lot of Zlatan media, not only in Sweden. But, with us, it is nothing."