Verizon late Tuesday said strong demand for 4G devices drove higher postpaid additions in the fourth quarter, but intense competition resulted in higher churn.

The U.S. telco giant said as much as 10% of its contract customer base upgraded to a new handset, higher than the 9.5% it predicted in early December. Verizon had 106.2 million retail wireless customers at the end of September.

"Churn was elevated both sequentially and year over year as a result of the highly competitive quarter," said Verizon, in a statement, adding that it maintained a disciplined focus on "high quality customers."

The combination of intense co mpetition and growth in phone upgrades will weigh on the company’s wireless EBITDA and service margin, Verizon said. However, it expects the picture to return to normal during the first quarter.

Verizon is due to publish its fourth quarter results on 22 January.

On Monday, Verizon’s CEO Lowell McAdam dismissed rumours that his company is in acquisition talks with AOL. He did concede though that the online media company is one of several that Verizon is considering as a potential partner.

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