By Katie Marsal

Published: 01:00 PM EST

With a little over three weeks to go before Apple's annual developers conference -- the same forum used to introduce the iPhone 3G last year -- AT&T is reportedly running out of current models and won't be restocking. (Updated with AT&T's official stance)

"I just got off the phone with AT&T regarding the death of my wife's iPhone and the customer service rep informed me they are no longer selling new iPhone 3G," said one subscriber familiar with the situation. "They have refurbs for sale."

Ask why there were no more iPhone 3Gs available, the representative for the exclusive U.S. carrier told the subscriber, who dialed 611 from his other AT&T handset, that he wasn't privy to details. The representative added, however, that he was told not to expect any additional stock of iPhone 3Gs.

(What's not clear is whether AT&T is holding back some remaining stock of new iPhone 3Gs for new customers who want to join the carrier's network for the first time.)

It's no secret that Apple is drawing down iPhone inventories ahead of third-generation hardware that is now increasingly looking as if it will be introduced on June 8th during the company's Worldwide Developers Conference, with availability likely to follow a few weeks later.

A little over a week ago, Apple made a move to clear some of its own iPhone 3G inventory by opening up sales of the handset to its online store customers, something it hasn't done since phasing out the original iPhone last spring. Meanwhile, it was reported just this week that one of the company's distributors in Australia has just a "few" weeks of inventory left and that the 16GB model has been officially discontinued.

Similar iPhone shortages cropped up last year in the weeks and months leading up to the introduction of the iPhone 3G.

Update: AT&T spokesman Brad Mays denies any shortage and claims that sales representatives provided "incorrect information," but doesn't elaborate further.