The European Commission has issued a statement of objections to Tronox regarding its proposed $2.4 billion acquisition of Cristal’s titanium dioxide (TiO2) business. Tronox is required to respond to the objections by early April.

“The statement of objections further details and clarifies the commission’s position, and receipt of it establishes a defined framework to move forward,” said Tronox CEO Jeffry Quinn. “We continue in constructive dialogue, and I am confident we can determine an appropriate and proportionate resolution to any valid concerns of the Commission.”

The mining and inorganic chemicals company added that the statement of objections does not prejudge the outcome of the Commission’s investigation nor the need to offer any particular remedy.

Tronox is already suing the US Federal Trade Commission (FTC) on the deal, alleging the agency is using delaying tactics to block the acquisition, which was originally announced in February 2017.

On Mar. 1, the companies extended their purchase agreement from May 21 to Jun. 30, with automatic three-month extensions perpetuating until Mar. 21 2019, to allow more time to secure the outstanding regulatory approvals.

The deal has already been cleared by the authorities in Australia, China, New Zealand, Turkey, South Korea and Colombia.