Budapest has slammed the travel restrictions on Hungarian citizens imposed by the US on Tuesday as Washington’s “revenge” over its refusal to provide the personal data of its citizens to American officials.

The restrictions are linked to the Visa Waiver Program (VWP) that allows the citizens of America’s allies – a total of 40 predominantly Western nations – to enter the US for business or tourism purposes for up to 90 days without needing to get a visa. Hungary was also on the VWP list.

Now, however, Hungarians can only travel to the US once within a period of one year under the Electronic System for Travel Authorization – an automatic mechanism that determines if a person can be allowed into the US under the VWP. For subsequent trips, Hungarians will have to re-apply for authorization and pay fees of between $4 and $21, depending on the decision issued in a particular case.