China has called in the South Korean ambassador to the country in retaliation for Seoul’s summoning of Beijing’s top envoy over his controversial remarks that seemingly warned Seoul not to bet against Beijing.

The Chinese foreign ministry said on Sunday that assistant foreign minister Nong Rong lodged a complaint with Ambassador Chung Jae-ho the previous day as he expressed grave concerns over Seoul's "unfair reaction" to a meeting between South Korean opposition leader Lee Jae-myung and Chinese Ambassador Xing Haiming.

The Chinese official stressed that maintaining contact and exchanges with various people in South Korea is a part of Xing's official duty aimed at promoting understanding and cooperation between the two sides.

The assistant minister urged Seoul to reflect the source of problems in bilateral relations, fulfill the spirit of the joint statement adopted when the two-way diplomatic ties were forged, and strive for the development of sound and stable relations.

On its website, the South Korean Embassy in China said Chung, on his part, lodged a protest and expressed serious concerns that Xing violated diplomatic protocol with remarks described as senseless and provocative that deviated from the truth.

The South Korean ambassador also expressed hope for enhanced communication in joint efforts to develop ties in a healthy and mature manner based on mutual respect, interests and reciprocity.

In a meeting with main opposition Democratic Party chair Lee Jae-myung last Thursday, Xing denied that his country is responsible for strained relations with South Korea and warned that betting on the U.S. over China would be a mistake.