Activision Blizzard CEO Bobby Kotick has spoken out about the sackings of Infinity Ward heads Jason West and Vince Zampella in a call to investors following the release of the company's Q1 financials.

Kotick explained that the decision to remove the pair had been a difficult one for him to make, especially since he had considered them friends on a personal level.

"The decision to remove the Infinity Ward executives was not taken lightly, and was not done to deprive them of their bonuses," he said, as reported by Eurogamer.

Referring to the counter-lawsuit Activision filed against West and Zampella last month, Kotick said their conduct had forced the company's hand.

"Once you begin to understand what has occurred, there was no grey area," he said. "There was no way to retain their services, as talented as they might have been."

"I personally consider both of them friends, and their conduct was a betrayal of that friendship," he added, before going on to say that he was "obviously upset" about the 35 other employees that had left Infinity Ward during the fallout.

"It is likely a few more will leave as well," he admitted. Although despite the situation he was optimistic about the future of the studio.

"The team at Infinity Ward today is comprised of some of the most talented people in the video game industry," he said, adding that Activision is "already strengthening the studio with additional talent and financial resources."

Infinity Ward is continuing to work on a new game for the Call of Duty franchise, while Call of Duty: Black Ops is in development with Treyarch and due out in November this year and a third game for the series is being made by Sledgehammer Games.

Cowen and Company analyst Doug Creutz said today that Activision had "aggressively addressed" the Infinity Ward issue, which pointed to an eventual revolve of problems within the studio.

"Activision aggressively addressed the recent Infinity Ward issue and clearly remains focused on insuring the health of its most important non-Blizzard franchise," he said.

"We continue to believe that the company will be able to navigate through any difficulties caused by Infinity Ward personnel departures."