Apple is set to rake in record revenues in the immediate aftermath of the iPhone 5S release date but there is one inner problem that could negatively impact on the tech giant's financial performance for calendar 2013, a new report said.

The push for its 2013 flagship release could lead Apple to total shipment of 62 million iPhones by the end of December 2013, according to Piper Jaffray analyst Gene Munster, also pointing to the obvious - that the iPhone 5S will banner the company's huge surge in the last three months of the year.

Mr Munster is so upbeat of the 5S prospect that his estimates exceeded that of market expectations, which is around 50 million units clearing the cash registers around the world for all circulating iPhone models - the iPhone 4, the iPhone 4S, the iPhone 5 and the latest build.

He warned, however, that the entry this year of the iPhone Lite could become problematic for the U.S. firm. True, the Lite will open up new frontiers for Apple, specifically in the so-called emerging markets, but it also could set off significant cannibalisation of iPhone's overall sales.

"We are assuming a 50 per cent cannibalization factor from the cheaper phone," Mr Munster was reported by CNET as saying, though he allowed that the forecast could be "too aggressive as we have yet to hear launch details."

Factoring in the iPhone Lite intrusion, Piper Jaffray remains confident that Apple would surpass the 47.8 million iPhones it pushed out in Q4 2012 by at least 17 per cent, meaning the company would still ship out some 56 million units of the core iPhone edition.

The budget iPhone build, on the other hand, will likely reach around 12 million units in sales by the end of the year, Mr Munster predicted.

Generally pointing to bright Apple prospects in the quarters ahead, his estimates fit in with the latest company results, which indicate that more than 31 million iPhones were sold as of the June 2013 quarter.

The numbers reflect a huge improvement from the 26 million units cleared in the same period in 2012, prompting Apple CEO Tim Cook to declare that so far, the iPhone 5 is the most popular iPhone model.

"We are laser-focused and working hard on some amazing new products that we will introduce in the fall and across 2014," Mr Cook was quoted by Apple Insider as saying.