Pressured by a surge in support for the far-right Freedom Party (FPO), Austria's government has repeatedly accused Hungary of letting migrants enter its territory in defiance of European Union rules that asylum seekers must stay in the first country they enter in the bloc.
Hungary, which is preparing for a referendum on whether to accept an EU-wide asylum quota, has countered that most refugees enter its territory from other EU states, notably Italy and Greece, in a growing European blame game.
"States or groups of states that permanently break the law have to expect legal consequences," Interior Minister Wolfgang Sobotka told ORF radio, responding to a question on Hungary's refusal to give ground.
"In that case, the (Austrian) republic must sue. The republic must see that the European Union acts according to the law, full stop."
Budapest has built a fence along its border with non-EU member Serbia to stem the flow of hundreds of thousands of people, many of them fleeing violence in the Middle East and North Africa. However, both Hungary and Austria said earlier this month the situation was now broadly under control.
A Hungarian government spokesman dismissed Sobotka's call in an emailed statement, saying the vast majority of migrants had arrived in other EU states first.
"Hungary cannot and will not take responsibility for, and suffer the consequences of, the irresponsible conduct of other member states - Austria, Germany - which expressly suggested ignoring the rules, or for other states - Greece - that neglected to do their job," the spokesman said.
