Kroger Co. (KR) on Tuesday countersued Albertsons (ACI), saying that the company should not receive a $600 million merger termination fee because its executives used a "secret and misguided campaign" to undermine the proposed business combination.

Albertsons terminated the proposed merger on Dec. 10 and filed suit in Delaware Court of Chancery, alleging that Kroger "willfully" tried to scuttle the transaction by ignoring input from anti-trust regulators and refusing to divest sufficient assets to allow the deal to proceed.

In its counterclaim, Kroger rejected those assertions, saying that while it was working diligently to close the merger, Albertsons was engaged with C&S Wholesale Grocers, the divestiture buyer, to pursue its own regulatory strategy, which ultimately undermined Kroger's efforts.

Kroger's counterclaim also asserts Albertsons had developed a "Plan B" to "sue Kroger in the event the merger failed to close, by manufacturing a paper-trail over many months including unfounded allegations."

Albertsons and C&S Wholesale Grocers did not immediately respond to a request from MT Newswires seeking comment on Tuesday.