Microsoft is reportedly still trying to reach a deal to buy Yahoo's search business, but is encountering little interest from Yahoo management.

Microsoft chief executive Steve Ballmer said in a conference call to journalists that he is still actively trying to find ways for Microsoft and Yahoo to work together.

But a CNBC report suggests that Microsoft executives have been repeatedly ignored by Yahoo since Carol Bartz became chief executive.

"Executives remain exceptionally frustrated that there has been no progress whatsoever even as Google continues to gain market share," said CNBC's Jim Goldman.

"It is just stunning to these people that nothing has been done, and it is almost a case of déjà vu that Microsoft wants some kind of conversation with Yahoo management, and yet Yahoo continues to circle the wagons, wanting to go it alone."

Ballmer explained that Microsoft is trying to stimulate its market share in the search industry, and will concentrate on the US market first of all. This would include better targeting of adverts, as well as limited new investment.

"I do not want to be known as the Jerry Yang of this market and keep investing with no returns," he said.

Ballmer also confirmed that the next version of Microsoft's Office suite, Office 14, will not be coming out this year.