Penguin Random House head Markus Dohle will step down at the end of the year after a U.S. judge blocked a planned $2.2 billion merger of the world's largest publisher and rival Simon & Schuster, the company said in a statement Friday.

He had resigned "at his own request and on the best of mutual terms," it added.

Nihar Malaviya, who is president and chief operating officer of Penguin Random House U.S., will take over as interim CEO from Jan. 1, the company said.

Thomas Rabe, chief executive of Penguin's German owner Bertelsmann, expressed full confidence in Malaviya, who he said had a chance of permanently becoming CEO. "We're looking at that over the next year," he told Reuters.

He said the company would focus on smaller and mid-size acquisitions in the United States and other countries.

"We will invest several hundred million euros in the acquisition of book publishers worldwide by 2025 as part of our Boost strategy," he said.

Bertelsmann initially said it would appeal the U.S. judge's decision but then last month decided to scrap the deal after discussions with Paramount Global, Simon & Schuster's owner.

Judge Florence Pan of the U.S. District Court for the District of Columbia ruled on Oct. 31 that the Justice Department had shown the deal could substantially lessen competition "in the market for the U.S. publishing rights to anticipated top-selling books."

With the deal's dissolution, Penguin will pay a $200 million termination fee to Paramount.

Regardless of the setback, Rabe said Bertelsmann wants to maintain its focus on the United States.

"We are by far the market leader there. Every acquisition, small or large, is very synergistic - on the cost and revenue side," he said.