(AP) -- Sprint is committing to buy more than 30 million iPhones over the next four years, imposing a heavy burden on an already cash-strapped company, The Wall Street Journal reports.

The paper cited unnamed sources. is expected to a reveal the first new model in more than a year on Tuesday.

Sprint shares dropped 10 percent on the news.

The paper earlier reported that Corp. will sell the phone, which previously was exclusive to AT&T Inc. and Verizon Wireless.

Apple and Sprint did not respond to requests for comment.

Sprint has 33 million subscribers on contract-based plans, so its reported commitment means it would have to convert half of them to iPhones, assuming they upgrade after two years.