Etihad Airways has started legal proceedings against airberlin’s administrator to fight the bankrupt German carrier’s attempt to retrieve €2 billion ($2.27 billion) in damages from its former shareholder.

Abu Dhabi-based Etihad began proceedings in the UK High Court in response to the lawsuit filed in Berlin last month by airberlin’s creditors, the airline confirmed in a Jan. 22 statement. Etihad claims the UK court has “exclusive jurisdiction over the dispute” and the Berlin case should be dismissed.

A Berlin court revealed in December it had received a claim from airberlin’s creditors for damages against Etihad that could amount to €2 billion. The claim relates to a letter dated April 28, 2017, in which the administrator said Etihad had agreed to “provide airberlin with the necessary support for the next 18 months, in order to enable its subsidiary to meet its financial obligations.”

The court’s statement said the administrator believed that, “contrary to this commitment, [Etihad] withdrew airberlin’s financial support in August 2017, with the result that airberlin had to file for bankruptcy.”

Etihad vowed at the time to fight the claim and is following through with its promise.

“The insolvency administrator’s case has no basis, and we are confident that we will prevail wherever the case is determined,” an Etihad spokesperson said.

Etihad said the Berlin filing breaches a jurisdiction agreement between Etihad and airberlin.

“Since Etihad’s initial investment in airberlin as a UK public company, our relationship has been formally governed by English law and has been subject to the jurisdiction of the English courts. Therefore, the High Court in London is the proper venue for this dispute,” the spokesperson said.

Etihad acquired a 29% stake in airberlin in 2011 as part of a strategy to increase its global presence by buying into foreign airlines. In addition to airberlin, the carrier took a 49% stake in Alitalia, which went on to file for bankruptcy protection in 2017. It also invested in Swiss regional carrier Darwin Airline, which it rebranded as Etihad Regional, before selling it to Slovenia’s Adria Airways.

The Etihad CEO who oversaw these investments, James Hogan, departed in early 2017 along with much of the senior management team after the carrier fell into the red. The airline is currently being restructured under new CEO Tony Douglas.

Kerry Reals,