South Korea has lodged a formal protest with Beijing demanding it address the growing issue of illegal fishing by Chinese fishermen in South Korean waters, a Seoul official said Wednesday.

The protest was delivered through diplomatic channels in the wake of the recent capture of Chinese fishing boats by South Korean fishermen near the inter-Korean border in the Yellow Sea, the official said on the condition of anonymity.

"We have persistently urged the Chinese side to draw up countermeasures to the illegal fishing activities," the official.

"We delivered the protest again and demanded countermeasures."

Chinese officials said they have been cracking down on such activity but face difficulties. Still, they said they would keep working to tackle the issue, according to the South Korean official.

The two countries have held regular talks involving officials from the foreign ministries, maritime law enforcement and fishery authorities.

In their last meeting in November, South Korea demanded practical measures from the Chinese to curb illegal fishing.

Their next meeting is scheduled to take place in South Korea at the end of this month or early next month where Seoul plans to further press the Chinese side to deal with the serious problem. (Yonhap)