Albertsons and Kroger terminated their $25 billion merger plan on Wednesday after courts blocked the deal, with the former suing its rival and alleging a breach of contract that led to the deal's demise.

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

Albertsons said Kroger has failed to make best efforts to secure regulatory approval of the merger of the supermarket chains.