Tech giant Samsung Electronics Co Ltd said on Wednesday shipments of the Galaxy Note 7 smartphone are being delayed as the firm conducts additional quality control testing for the premium device.
The firm also said Galaxy Note 7 shipments to South Korea's top three carriers - SK Telecom Co Ltd, KT Corp and LG Uplus Corp - had been halted.
"Shipments of the Galaxy Note 7 are being delayed due to additional tests being conducted for product quality," Samsung said in a statement to Reuters.
The firm did not elaborate on what potential problems it was testing for or whether shipments to other countries were being affected. South Korean media reports have said some users have claimed that the battery exploded.
Quality control problems, if confirmed, could deal a major blow to the world's top smartphone maker, which was counting on the Galaxy Note 7 to help maintain sales momentum in the second half when competition is expected to intensify.
The phone, which launched in South Korea and other markets on Aug. 19, retails at 988,900 won in South Korea.
Production problems for the curved displays for the Galaxy S6 edge phone resulted in disappointing sales last year, and Samsung risks a repeat this year if it cannot address the Galaxy Note 7 supply problems quickly. Rival Apple Inc is expected to unveil its new phones next week.
Hyundai Securities said in a report released on Thursday that the Galaxy Note 7's problems appeared to be related to modules or parts, and that such "malfunctions" should be resolved quickly.
"Such problems can be addressed by replacing parts and modules and changing the design of circuits, so supply problems for the Galaxy Note 7 should ease within a matter of few weeks," the brokerage said, retaining its third-quarter operating profit forecast of 8.5 trillion won.
It was not immediately clear when Galaxy Note 7 shipments to South Korean carriers would resume.
Samsung has said demand for the new phone is far exceeding demand, creating a shortage and forcing it to push back the launch in some markets. The firm has said it is utilizing all possible means to boost production.
Samsung's other premium smartphone models that launched in March, the Galaxy S7 and S7 edge, have been huge hits with customers and lifted earnings in the first half.