While many analysts are debating when Apple's shares may hit the magical US$1000 mark, one advisor has downgraded his rating of the company, saying telecommunications companies are tired of offering aggressive deals to win over prospective buyers.

As reported by both Apple Insider and Cult of Mac, Walter Piecyk of BITG Research has changed his recommendation of Apple stock from ‘buy' to ‘neutral', telling clients that subsidies from telcos have fuelled uptake of the iPhone ‘since its inception'.

However, these subsidies are costing the telcos a fortune, especially with the frequency of iPhone model upgrades.

"Wireless operators have been happy to subsidise smartphones to new and existing customers in order to provide a lift to the average monthly bill of their customer base,” Piecyk syas.

"The cost to drive that ARPU (Average Revenue Per User) accretion is now starting to eat away at profitability and the performance of those stocks... We expect those policies to change, as the faster upgrade rate of smartphones compared to legacy feature phones has been a costly surprise to post-paid and pre-paid operators alike.

Apple shares are currently valued at a massive US$636.23, equating to a market cap of US$593.2 billion.