South Korean mobile operators ended lower on the Seoul main stock index on Wednesday following government remarks on tightening regulations on smartphone subsidies.

During a briefing on President Park Geun-hye's first cabinet meeting, spokeswoman Kim Haing said the government is seeking to draw up measures to curb excessive subsidies involved in mobile phone sales.

Top mobile carrier SK Telecom Co. slipped 0.27 percent to 183,000 won, while No. 3 player LG Uplus Corp. lost 1.03 percent to 8,660 won. KT Corp., the country's top fixed-line and No. 2 mobile operator, however, gained 0.41 percent to 36,900 won.

The remarks come a day before KT resumes business operations on Thursday. The telecom giant was banned from attracting new subscribers for 20 days as part of the Korea Communications Commission (KCC)'s business suspension on the country's three mobile operators.

In December, the communications watchdog slapped the companies a combined 11.89 billion won (US$10.84 million) in fines in addition to business suspensions for doling out excessive subsidies to lure new subscribers.

The KCC said it found the three mobile carriers had discriminated against subscribers by paying subsidies of more than 270,000 won to certain users between July and December last year.

Smallest player LG Uplus was first suspended for 24 days from Jan. 7 to Jan. 30, while top player SK Telecom's 22-day suspension ended on Feb. 21.

The mobile carriers, however, continued their subsidy spree and fired criticism at each other for overheating the market, raising doubts on the validity of the regulatory move and the feasibility of the 270,000 won cap.

Industry officials have been claiming the current guideline is inadequate given the rising price of smartphones. Flagship handsets such as Samsung Electronics Co.'s Galaxy S line-up and LG Electronics Inc.'s Optimus G line-up are mostly priced at the 900,000-won level.

The KCC is scheduled to address the sales subsidies of the three mobile operators and decide on countermeasures at its March 14 meeting. (Yonhap News)