Three of Apple's top executives Peter Oppenheimer, Ron Johnson and Eddy Cue refused to be drawn on the iPhone 5 launch date when questioned by Morgan Stanley analyst Katy Hubert, according to a report.

According to the World of Apple website, Huberty "pressed Apple on rumours of a later than normal iPhone launch but got no answer".

Huberty did reveal that Apple told her that the company follows product cycles "driven more by software than hardware", which could mean that it is iOS 5, rather than the iPhone 5 itself, that is causing the delays.

Apple tends to announce iPhone launches at the June WorldWide Developer Conference (WWDC) though is not thought to be launching the iPhone 5 when this year's WWDC convenes at the Moscone Center in San Francisco.

Instead, most speculators now believe Apple will launch the iPhone 5 in September, or perhaps even 2012.

Jonny Evans - Apple iPhone 5 is nowhere near production

Huberty reportedly left the meeting with "increased confidence", predicting that iPhone sales would grow 55 percent per annum over the next two years, with iPad sales growing by 74 percent and Mac sales up 17 percent over the same period.