Ireland’s government will this week formally submit its appeal against the European Commission’s multi-billion-euro demand for back taxes from Apple, Finance Minister Michael Noonan said on Tuesday.

Ireland’s cabinet agreed in September to join the iPhone maker aapl in appealing the Commission’s order that the U.S. tech giant pay up to 13 billion euros to Dublin after ruling the firm had received illegal state aid.

Dublin is seeking to protect a tax regime that has attracted many multinational employers. The European Commission decision has also angered Washington, which accuses it of trying to grab tax revenue that should go to the United States.

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“The government fundamentally disagrees with the European Commission’s analysis and the decision left no choice but to take an appeal to the European Courts and this will be submitted tomorrow,” Noonan told a European Parliament committee in Brussels.