NEW YORK (Reuters) - Activist investor Jeffrey Smith, head of Starboard Value LP, said Staples Inc's <SPLS.O> deal to buy Office Depot Inc <ODP.O> would likely be approved by regulators.

"We believe that it's likely that it goes through," Smith told cable television network CNBC. Starboard had a 4.5 percent ownership stake in Staples as of March and boosted its holdings in Office Depot to nearly 10 percent in December.

Smith, whose firm is also a Yahoo Inc <YHOO.O> shareholder, said a merger between the company and AOL Inc <AOL.N> still had benefits but that it would make more sense after Yahoo finished spinning off its stake in Alibaba Group Holding Ltd <BABA.N.>.

(Reporting by Sam Forgione; Editing by Chizu Nomiyama)