The chief executive officer of Kroger insisted Wednesday that merging with rival Albertsons would allow the two supermarket companies to lower prices and more effectively compete with retail giants like Walmart and Amazon.

Kroger CEO Rodney McMullen argued in favor of what would be the largest grocery chain merger in U.S. history while testifying during a federal court hearing in Oregon on the U.S. government’s request for a preliminary injunction that would block the $24.6 billion deal.