Korean mobile carriers SK Telecom Co. and LG Uplus Corp. said Tuesday they plan to kick off voice over long-term evolution (VoLTE) services this week, a move that comes amid heightened competition to lure users to the faster and more lucrative network technology.

The VoLTE service, which offers voice calls through fourth-generation LTE networks, enables clearer quality and faster connectivity than services on the existing third-generation (3G) network.

Current technology only enables data transmission via an LTE network, which is why market watchers believe VoLTE will significantly boost demand for smartphones and services operating on the fastest mobile network.

Top player SK Telecom and smallest player LG Uplus are set to offer the world's first commercialized VoLTE service via the Galaxy S3 and Optimus LTE 2 smartphones starting Wednesday, the two companies said in separate statements.

Users can purchase smartphones packed with the VoLTE software or download the software on their LTE devices, according to the two companies. The software updates will be available within this month.

Both companies pledged to expand the lineup of smartphones that support the VoLTE service. LG Uplus said it plans to unveil at least seven models this year that enable the service, while SK Telecom said it plans to upload the feature on most of its future lineup.

The two mobile carriers also said they plan to develop more services that combine VoLTE with other mobile functions such as data sharing.

As two of the country's three mobile carriers are set to provide VoLTE service, subscribers of different companies are likely to be able to call each other via the new service as early as October.

KT Corp., the country's top fixed-line operator and No. 2 mobile carrier, earlier said it plans to commercialize the service in October following a pilot program that kicked off in July.

South Korean LTE subscribers are one of world's fastest-growing LTE user groups. Local mobile carriers plan to ramp up subscription to 16 million by the end of this year, which means Koreans will account for roughly one-third of the global total, according to industry data.

As of the end of July, the number of LTE subscribers at the country's three mobile carriers stood at 8.7 million. (Yonhap)