Apple Inc. is predicting initial sales of its new iPhone models will top last year’s opening-weekend record, thanks largely to demand in China.

Preorders for iPhone 6s and 6s Plus were “very strong” and sales are on pace to exceed last year’s launch-weekend record of 10 million handsets, Apple said on Monday. The devices, unveiled at an event in San Francisco last week, will hit stores on Sept. 25.

The strong demand was aided by orders from China, which this year was added as one of the countries to sell the smartphone at its introduction. Gene Munster, an analyst at Piper Jaffray Cos., said orders may be roughly flat if customers in China weren’t included in the initial availability. Munster is predicting opening-weekend sales of as many as 13 million units, with China accounting for about 2 million shipments.

Maintaining healthy demand for the iPhone is critical for Apple, which got more than 60 percent of its revenue from the handsets in recent quarters. Analysts have questioned whether the new models will be able to match the success of last year’s record-setting release, when the company overhauled the design of the device with bigger screens. Walter Piecyk, an analyst at BTIG in New York, said the early figures “should not be taken as strong evidence” that iPhone sales will exceed last year’s record output.

Shares Rise

Apple shares rose 1 percent to $115.31 at the close in New York. The shares have fallen 12 percent since July 21, when Apple released financial results that were lower than analysts anticipated, sparking concerns about the company’s ability to keep up its torrid growth year after year. An economic slowdown in China, the company’s second-biggest market after the U.S., has added to the investor hand-wringing.

Unlike last year, when Apple said it sold more than 4 million units during the first 24 hours of orders, the company didn’t give numbers this year. “Customer response to iPhone 6s and iPhone 6s Plus has been extremely positive and preorders this weekend were very strong around the world,” Apple spokeswoman Trudy Muller said.

The new iPhone models add an improved camera, faster processor and a new feature called 3D Touch that provides shortcuts to common tasks when applying stronger pressure to the screen. In addition to the U.S. and China, the handsets will be available in Australia, Canada, France, Germany, Japan, New Zealand, Puerto Rico, Singapore and the U.K.