South Korean authorities on Wednesday halved the daily limit on text messages sent out by mobile phones as part of a campaign against spam, officials said.

The number of text messages that a mobile user can send out a day was restricted to 500, down from 1,000, beginning Wednesday, the Korea Communications Commission said.

The commission said the previous ceiling had been abused by spammers and was ineffective in cutting down on the junk mail.

The spreading of spam to people without consent is banned and subject to a heavy fine in South Korea, but the practice dies hard.

South Korea had 47.7 million mobiles registered for use as of October, accounting for 98 percent of the total population.