BEIJING, June 25 (Xinhuanet) -- Virgin Mobile USA is adding to the cell phone carrier price-cutting wars sweeping the United States by introducing a plan with unlimited calling for 79.99 U.S. dollars a month.

    The prepaid plan will be available July 1, the carrier said. Virgin was charging 99.99 dollars for 1,000 minutes per month with no limit on night and weekend calls.

    Verizon Wireless introduced a plan with unlimited nationwide calling in February for 99.99 dollars per month that was quickly matched by its competitors.

    Sprint Nextel Corp., whose network Virgin Mobile uses, charges 89.99 dollars for its own unlimited plan, which includes free messaging. Virgin Mobile charges 10 dollars extra per month for unlimited messaging. The prices do not include taxes and fees that can add up to $10 a month.

    Virgin Mobile may be hoping with its new plan to reap a sales boost as Verizon Wireless and AT&T have since they introduced their comparable plans in February. Both carriers said more people upgrade to the unlimited plan than downgrade from more expensive plans.

    The average revenue per user at Virgin Mobile was $19.93 per month in the first quarter, less than half of the average charges at the larger carriers. It had 5.1 million customers at the end of March, making it one of the largest U.S. "mobile virtual network operators," or MVNOs. Rather than owning their own network, MVNOs buy wholesale airtime from other carriers.

    However, Virgin Mobile expects to lose subscribers in the first quarter. It is talks with South Korea's SK Telecom Co., majority owner of Helio, another struggling MVNO. The talks could mean a combination of the two carriers.

    (Agencies)