The company plans to slash the first quarter production target of the 10th anniversary iPhone to around 20mln units from 40mln, Japanese newspaper Nikkei reported.
Apple is expected to maintain its total production of 30mln units for its lower-priced iPhones, including the 7 and 8 models, in the first quarter.
The news comes ahead of Apple’s results for its fiscal first quarter.
Analysts expect the company to report record-breaking profits of US$19bn, boosted by sales of the new smartphone, which starts at a hefty US$999 price tag.
Apple struggled to meet demand for the iPhone X immediately after its launch but sales are understood to have softened in recent weeks as more cash-conscious consumers opt for the cheaper models.
Sluggish sales of the iPhone X could result in a delay to Apple’s plans to introduce OLED screens in other iPhone models, according to Nikkei.
The iPhone X features facial recognition, back-to-front durable glass, water and dust resistance and wireless charging but has drawn criticism for its lack of new technologies compared with previous models and its rivals.
In China, a market Apple has struggled to crack, consumers are said to have complained that the screen has less usable space than on the iPhone 8 Plus.
Shares closed down 2.07% to US$167.96 each in US on Monday.
On Tuesday, Apple shares in New York shed 1.36% to US$165.74.