Speaking to the Associated Press, AT&T spokesman Fletcher Cook said the limited availability will only be for the initial launch. Later, it will be sold on AT&T's Web site and through other outlets, he said.
AT&T owns 1,800 retail stores that will be carrying the inaugural Apple handset when it goes on sale later this month, in addition to approximately 170 Apple-owned retail stores.
But AT&T also works with thousands of other franchise outlets that carry the AT&T or Cingular name, the AP noted. In all, the No. 1 U.S. wireless has 8,000 franchise outlets and retail carriers.
Cook did not specify how many of those partner locations may begin to carry the iPhone in the months ahead, nor did he reveal a specific timeframe for the expanded distribution.
iPhone is due to go on sale beginning 6:00 p.m. local time on Friday, June 29.