Irish football fans won't receive the céad míle fáilte when they arrive to Copenhagen.
They are being warned they will be refused entry for Saturday's game in Denmark if they have not purchased their tickets through the FAI.
The Danish Football Federation says as many as 1,000 Irish fans who bought tickets for sections of the ground designated for home supporters will not be allowed in.
2,412 tickets for the away section at the Parken Stadium have been distributed by the FAI.
Some Irish fans opted to buy tickets online when the FAI allocation ran out. Officials at the Danish FA are warning that they will not be permitted to enter the ground.
Danish Football Federation’s communications director said:“We have contacted a number of Irish fans to tell them they are not able to use the tickets, we will offer them a refund for the money.
“We were quite clear about what would happen if you showed up wearing a green jersey, it’s a question of security. We don’t want to have a security issue where Irish fans could get in trouble, not because Irish fans are trouble makers.
“If they are in the middle of the Danish section and you imagine if Ireland score a goal and four or five Irish fans are joyous about it and they are in the middle of a lot of disappointed Danish fans it could create tension.
“We don’t want to create tension and we don’t want to risk that, that is why we are doing it.”