According to a report in Fortune late on Monday, the usual September launch may be delayed to October or November because of the complications that stem from the new OLED screen and the changes required to sensors and cameras.

"The processing chip running the phones, Apple's custom A11, is also being manufactured on new 10-nanometer scale equipment, further complicating matters," the report quoted analyst Ming-Chi Kuo as saying.

Ming-Chi Kuo is an analyst for KGI Securities, a financial services group in the Asia-Pacific region.

It is, however, expected that the delay in iPhone 8 will not affect new lower-end editions as they will not feature new screens and will largely resemble the exterior design of the past three iPhone models, the report added.

Apple has not disclosed anything so far about the new iPhones or the about the launch date.

The rumours of Apple facing possible production delays with iPhone 8 has been circulating in the tech arena for a couple of weeks.