The number of Internet phone users in the country has topped three million.

Eleven Internet phone operators, including LG Dacom and KT, said Sunday that more than two-and-a-half million people were subscribers to Internet phone service at the end of last year, and that the figure rose to three million just two and a half months later.

The service allows Internet users to make or receive calls online.

A source at an Internet phone operator said the number of Internet phone users will top five million by the end of this year.

The number of landline phone users slid to 19 million, with some 140-thousand dropping the service last month alone.