Rep. Cho Kyung-tae, head of the South Korea-Taiwan inter-parliamentary friendship group / Yonhap

The Chinese Embassy in Seoul on Thursday protested strongly against a South Korean parliamentary delegation's recent visit to Taiwan, calling it a "serious violation" of their bilateral joint agreement.

According to Taiwan's foreign ministry, the delegation of the South Korea-Taiwan inter-parliamentary friendship group, led by Rep. Cho Kyung-tae of the ruling People Power Party (PPP), visited Taipei from Dec. 28-31.

Other members included Rep. Chung Woo-taik, deputy speaker of the National Assembly, and Rep. Lee Dal-gon of the PPP.

"This is a serious violation of the 'One China' policy and the spirit of the joint statement on diplomatic relations between China and Korea, and runs counter to the development of the friendly ties," an embassy spokesperson said in a statement.

China expresses "firm opposition and strong protest" over the visit, the embassy added.

It then urged Seoul to take "timely measures to alleviate the negative impact" of the visit and to refrain from engaging in any "official exchanges with the Taiwan region," saying it has already voiced its complaint to the South Korean government.

During their trip, the delegates met with Taiwanese President Tsai Ing-wen and Legislative Speaker You Si-kun, and also discussed the North Korea issue with the Mainland Affairs Council, Taiwan's China-policy making body, according to the Taiwanese foreign ministry.

Their low-key visit came after U.S. House Speaker Nancy Pelosi's trip to Taiwan in August last year, which prompted strong objection and large-scale military exercises from China amid the growing rivalry between Washington and Beijing. (Yonhap)