Microsoft CEO Steve Ballmer is explaining his view of the Internet search market and the company's pursuit of Yahoo, which has been the biggest story in the tech world for the first half of the year.

Ballmer repeated his mantra: Yahoo was a tactic to quickly build the scale necessary to compete in search and search advertising, but it wasn't the company's strategy.

The company was ready to spend "$40 whatever blah-blah billion for Yahoo," he said. Because it's no longer doing that, the company has more flexibility to reinvent the search and advertising model, Ballmer said.

He said there's "nothing under discussion between the two of us," but did not rule out the possibility of future discussions.

One big reason Microsoft backed off its proposal to buy the whole company was the delay in moving a transaction forward, which would have pushed the regulatory review process into the next U.S. administration. Ballmer said the company had a tight time line and wanted to go through regulatory review of a potential acquisition with one administration, not two.