Kroger, the nation’s largest operator of traditional supermarkets, would buy Albertsons, the second-largest such operator, for $24.6 billion and merge it into Kroger’s operations. The deal would combine Cincinnati-based Kroger and its 2,722 stores with Boise, Idaho-based Albertsons and the 2,271 stores it operates.

In an unsealed complaint, Albertsons claims that Kroger’s hubris and reluctance to divest of stores sank their merger; Kroger has said its rival breached the agreement.

Albertsons’ breach-of-contract claims, filed in a Delaware chancery court Dec. 11, allege Cincinnati-based Kroger “put itself first” in the face of regulatory opposition to the merger and ignored Albertsons’ suggestions for how to get the deal approved.