Apple has sent emails to those registered to , warning them that any documents stored in the online service need to be downloaded and saved onto a computer before the end of July, as they will no longer be accessible after 31 July.

"Remember, as of 31 July 2012, you will no longer be able to access your documents on the iWork.com site or view them on the web," reads Apple's email. "Moving forward, you can use iCloud to store your documents and make them available across your computer and your iPhone, iPad or iPod touch."

Apple has provided users with a with instructions about how to save documents from iWork.com onto a computer.

At June's Worldwide Developers Conference, Apple vice president of software engineering Craig Federighi revealed that via Documents in the Cloud will be arriving this summer with OS X 10.8 Mountain Lion.