The deal will make Twitter messages more visible on the Internet, according to reports by Bloomberg News and The New York Times, with tweets showing up in Google searches as soon as they are posted.
"I do want to confirm that we have a relationship that we have agreed to with Google," Costolo said during a quarterly earnings call with analysts.
"I don't have any more details to share with you at this time."
Deutsche Bank analyst Ross Sandler said in a research note that the tie-up "could be the catalyst to push shares meaningfully higher," and help Twitter add users.
When pressed, Costolo said that renewing its alliance with Google was driven, in part, by the opportunity to drive tremendous amounts of attention to Twitter given the online search giant's scale and scope.
"This is not something that you are going to see launched or rolled out for several months," Costolo said. "I just want to make that very clear."
Twitter chief financial officer Anthony Noto declined to provide analysts perspective on any revenue considerations stemming from the Google alliance.
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