Differences still exist among World Trade Organization (WTO) members in the expansion of the Information Technology Agreement, WTO Director-General Roberto Azevedo said Monday. "There are still a few remaining points I think from the negotiating partners to get there," Azevedo told the U.S. Chamber of Commerce. "It's difficult to tell at this point in time how quickly and how far we can get from where we are at this point in time," he added. The agreement, which aims to reduce tariffs on IT products to zero, came into effect in 1997. Members joining the agreement export 97 percent of the world's IT products. Considering technological improvements, WTO members decided in 2012 to expand the agreement to cover more IT products. Azevedo said he had talked with the major negotiating countries and detected some positive signals. "I think there is a positive attitude. But like in every other negotiation, there are difficulties and these difficulties are trying to be overcome as quickly as possible," he said. According to the U.S. Chamber of Commerce data, a commercially significant expansion of the agreement could add an estimated 190 billion U.S. dollars to global gross domestic product annually.