American reports had pointed to a September 21 release for the new iPhone in the US, but it was unclear whether international launches would be delayed, the Telegraph reports.
Earlier, Apple invited journalists and industry observers to a special event in San Francisco.
The invite showed a number 12, casting a shadow in the shape of a 5.
The text on the invite said, 'It's almost here,', which many observes said was an indication of the firm's plan to unveil iPhone5.
In addition to the new iPhone, Apple is likely to confirm the release of iOS 6, the latest version of its mobile operating system.