Rupert Murdoch has withdrawn plans to merge News Corp. with Fox Corp., abandoning a deal that had drawn significant criticism from shareholders.

In a brief announcement Tuesday, Murdoch did not give a reason for the change of heart beyond commenting that “a combination is not optimal for shareholders” of each company at the current time.

Irenic Capital Management, Independent Franchise Partners, and T. Rowe Price Associates had all opposed the deal, reckoning that News Corp. shares would probably be undervalued and litigation against Fox could hurt News Corp.’s interests. Two of the activists suggested a mixture of asset sales to help News Corp.’s share price.

In a statement Tuesday afternoon, Irenic called Murdoch’s step back ”the right decision,” adding that News Corp. should now focus on unlocking trapped value within its ”exceptional – yet disparate – collection of assets and businesses.” Irenic suggested the process should start with the company’s Australian digital real-estate firm REA Group, and the Dow Jones unit, which publishes The Wall Street Journal. Irenic owns 2.6% of News Corp.’s class B voting stock.

Shares in News Corp. fell as much as 2.3% in after-hours trading before rebounding, while shares in Fox Corp. were up 1.67%.