Apple Inc. (NASDAQ:AAPL), which announced its new iPhone 6 and iPhone 6 Plus models last week, is expected to break its previous records by selling as many as 60 million iPhones during this year’s holiday season, a new report said Monday. The company had earlier announced that demand for the new iPhone 6 models had topped 4 million units in the first 24 hours after opening them up for pre-orders.

According to Apple’s announcement, first-day pre-orders for the iPhone 6 and iPhone 6 Plus set a new record for the company, generating twice the number of pre-orders as the iPhone 5, which pulled in 2 million pre-orders in 2012. Apple also said that its initial supply of new iPhone units was quickly sold out across all retailers, and customers would be able to purchase the devices from Apple Stores and retail partners after they are officially released Friday.

Rob Cihra, an analyst at Evercore Partners, estimates that the successful start will help Apple ship a total of 37 million iPhones in the September quarter, representing an annual growth of 10 percent and setting a new record for the three-month period, Apple Insider reported, adding that the company’s pre-order announcement on Monday has forced analysts to revise their estimates for the holiday season.

According to Apple Insider, investors are keen to know how the company will perform in the December quarter, which will be the first full quarter after the iPhone 6 hit the market.

While Cihra expected Apple to report an annual growth of 22 percent in the December quarter and ship 62 million iPhones in the period, Gene Munster of Piper Jaffray projected about 59 million iPhone shipments in the same period. Meanwhile, Keith Bachman of BMO Capital Markets expected that the iPhone 6 Plus could cannibalize sales of Apple's 7.9-inch iPad mini, Apple Insider reported.

Both versions of the iPhone 6 will be launched in Australia, Canada, France, Germany, Hong Kong, Japan, Puerto Rico, Singapore, U.S. and the U.K. on Sept. 19.

The devices are expected to be available in another 20 countries, including Austria, Belgium, Denmark, Finland, Ireland, Isle of Man, Italy, Liechtenstein, Luxembourg, Netherlands, New Zealand, Norway, Portugal, Qatar, Russia, Saudi Arabia, Spain, Sweden, Switzerland, Taiwan, Turkey and United Arab Emirates, starting Sept. 26, only a few days ahead of the end of the September quarter.