In an historic ruling for labor and antitrust advocates, a federal judge blocked the $25 billion merger of grocery giants Kroger and Albertsons.

Albertsons has terminated its planned merger with Kroger and is suing Kroger for alleged breach of the merger agreement, claiming it had failed to make its “best efforts” to get the merger approved. The planned merger was doomed after a judge on the U.

Kroger's $24.6 billion acquisition of Albertsons was blocked by a federal judge. Lawyers for the companies previously said this would sink the deal.