Austrian Chancellor Sebastian Kurz's government argues the new system will prevent abuse of its welfare system | Frederick Florin/AFP via Getty Images Brussels takes on Vienna for cutting benefits to foreign children ‘There are no second-class children in the EU,’ commissioner says.

The European Commission launched a legal procedure on Thursday against Vienna for reducing child benefits to Austrian-based foreign workers whose children live in poorer EU countries.

Under a measure introduced this month by the government of conservatives and the far right, Vienna links benefit payments for children who live in other EU countries to the cost of living in those countries — even though their parents pay the same taxes and social security contributions as Austrian citizens.

Chancellor Sebastian Kurz's government argues the new system will prevent abuse of its welfare system. “It is an unfairness built into the system that, for two children who do not even live in Austria but in Romania, roughly €300 a month are transferred to Romania and that is almost the average income there,” Kurz told reporters last year.

But the policy has elicited anger from the EU's eastern states. Slovenia, Bulgaria, Lithuania, the Czech Republic, Slovakia, Hungary, and Poland wrote to the European Commission protesting against the new rules late last year.

The Commission made clear on Thursday it agrees with the critics and launched so-called infringement proceedings — a series of steps that Brussels takes when it believes EU law is being broken. The procedure can ultimately lead to the Commission taking a government to the European Court of Justice.

“Our single market is based on fairness and equal treatment," said Marianne Thyssen, the European employment commissioner.

"When mobile workers contribute in the same way to a social security system as local workers, they should receive the same benefits, also when their children live abroad. There are no second-class children in the EU," she said.

The government in Vienna now has two months to address the European Commission's concerns.