AT&T Inc plans to expand sales of netbook computers to all its stores in an effort to expand wireless services beyond cell phones.

Ralph de la Vega, the head of AT&T's consumer business, said on Tuesday that the U.S. phone company would directly sell netbooks from Dell Inc, Acer Inc and Lenovo Group Ltd starting this summer.

Until now, only AT&T stores in Atlanta and Philadelphia, and consumer electronics retailers RadioShack Corp and Costco, have been selling the netbooks, which come with AT&T mobile data connections.

We're taking broadband and really making it mobile, de la Vega said at the Reuters Global Technology Summit in New York.

While sales of netbooks are expected to be boosted by promotions from carriers, some analysts have said that consumer enthusiasm could be muted by the requirement to sign up for two-year wireless service contracts and the $60-a-month data connection fees that come with the devices.

AT&T said in April it was testing a $40-per-month fee for 200 megabytes of data downloads to netbooks, or about 1/25th of the downloads allowed under the $60 service.

AT&T's bigger mobile rival Verizon Wireless, a venture of Verizon Communications Inc and Vodafone Group Plc, started selling netbook computers from Hewlett-Packard Co earlier this week.

(Reporting by Sinead Carew, editing by Tiffany Wu, editing by Matthew Lewis)