Apple reported that its online stores in the US and UK are sold out of the iPhone, an Associated Press report said.
The development is seen as a sign supplies are being winnowed ahead of the launch of the device's next generation featuring faster internet surfing speeds, the report added.
The US-based company confirmed that the iPhone is out of stock online, but added that brick-and-mortar stores run by Apple and iPhone carriers including AT&T might still have units available, the report said
Apple has been known for clearing out its inventory of a certain product ahead of a major upgrade.
Apple spokeswoman Natalie Kerris declined to comment on reasons for the shortage and on Apple's plans for an update to the device, which is widely expected to be unveiled in June at Apple's Worldwide Developers Conference in San Francisco.
The paucity of iPhones for sale in some markets comes as Apple is hustling to meet its goal of selling 10 million of the hybrid iPod-cell phone-internet surfing gadgets by the end of 2008, the Associated Press report said.
So far, Apple has sold 5.4 million iPhones, according to the latest data as of the end of March, it added.
The exclusive deals for the iPhone were with AT&T Inc. in the US, O2 in Britain, T-Mobile in Germany and France Telecom's Orange wireless arm in France.