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BEIJING, Jan 16 (Reuters) - Apple's smartphone shipments in China plunged 25% in the fourth quarter of 2024, data from research firm Canalys showed, as the iPhone maker faced mounting pressure from a resurgent Huawei in one of its biggest global markets.

The U.S. tech giant shipped 13.1 million units in China during the period, narrowly maintaining its market lead with a 17% share, according to Canalys data released on Thursday.

Huawei captured 17% market share on shipments of 12.9 million units, placing it in a virtual tie with Apple for market leadership, the Canalys data showed.

Huawei, which posted a 24% rise in shipments in the fourth quarter, has emerged as a particularly strong challenger since its return to the premium segment in August 2023 with locally-made chipsets.

Apple has turned to rare discounts to stimulate sales amid growing competitive pressure. The company launched a four-day promotion in China from Jan. 4-7, offering price cuts of up to 500 yuan ($68.50) on its iPhone 16 models through its official channels.

Major Chinese e-commerce platforms have followed suit with their own promotions. Alibaba's Tmall marketplace announced discounts of up to 1,000 yuan ($137) on iPhone 15 series devices.

"While Apple and its iPhone 15 series maintained their leadership in the fourth quarter, they face mounting pressure from domestic flagship devices," Canalys analyst Amber Liu said.

"Beyond seasonal promotions, Apple is enhancing its competitive position and user retention in China's premium segment through improved retail experiences, trade-in programs, and expanded interest-free installment plans."

Annual shipments of smartphones in China in 2024 increased 4% year-over-year to 285 million units.

(Reporting by Liam Mo and Brenda Goh; Editing by Kim Coghill and Jamie Freed)

((liam.mo@thomsonreuters.com;))