Sprint Nextel Corp has agreed to buy at least 30.5 million iPhones over the next four years, involving a commitment of about $20 billion, whether or not its customers want to buy the devices, according to a Wall Street Journal story.

Sprint shares fell more than 8 percent on Monday after the report, which cited unnamed people familiar with the matter.

Representatives for Sprint were not immediately available for comment. The company has not confirmed widespread speculation that it will distribute the next model of Apple Inc's iPhone, expected to be announced October 4. Sprint shares were down 26 cents to $2.78 on the New York Stock Exchange after the report.