The tech giant on Tuesday was expected to sign an agreement with Ireland finance minister Paschal Donohoe to set up a tax-repayment plan worth 13 billion euros ($15.9 billion), according to the Financial Times. Apple is expected to pay those back taxes in full by September. However, the funds will be held in escrow in Ireland until a case between Apple and the EU’s competition watchdog, the European Commission, is settled.

The Commission slapped Apple with its massive tax bill in 2016 after it charged the company with obtaining illegal state aid from Ireland to significantly reduce its tax burden. While both Apple and Ireland have said that the agreement between them was legal, the Commission argued that Apple has illegally sidestepped steep tax bills and must pay up.

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Apple has said that it pays its fair share of taxes and in the U.S., is the biggest taxpayer. Apple CEO Tim Cook has called the Commission’s charges “maddening” and has promised to fight the case to its bitter end.

In December, however, Apple was ordered to pay the tax levy while it continues to battle its case in European courts. The cash will be kept in an escrow account, where it will stay until one side wins. That likely won’t happen anytime soon, however, since most industry experts believe the case will continue to be litigated for several years.

Apple did not immediately respond to a Fortune request for comment on the apparent escrow deal with Ireland.