South Korean presidential hopeful, Moon Jae-in urged China on Tuesday, (14 March) to halt the economic retaliation against South Korean companies over the deployment of Terminal High Altitude Area Defense (THAAD).

In a debate with other presidential candidates, he said that Seoul should stand up to Beijing but he added that diplomatic efforts should also be made to reach a solution.

"We should complain about what needs to be complained about and we should make diplomatic efforts to persuade China," he said.

"It is also not desirable for China to harm our relationship with excessive retaliation. I call on China to immediately stop," Moon added.

China, in recent days, has ramped up pressure and placed constraints on some organisations doing business with South Korea. Many in South see the latest economic restrictions by China as its retaliation against the deployment of Thaad.

However, Finance Minister Yoo IL-ho on Monday said that they did not have enough evidence of China's retaliation and Beijing has not directly said that it is taking aim at South Korean companies.

The presidential candidate, who has been leading in polls, is a popular liberal politician and a human rights lawyer. He said that the government had not handled the deployment of the defence system in a proper manner and rushed into it without public consensus.

Beijing is against South Korea's agreement with the US to deploy Thaad. Washington and Seoul say that the system is for the defense against North Korea but China fears that the system's radar could penetrate Chinese territory.

The US started the deployment over a week ago, just a day after Pyongyang test-fired four missiles.

Moon Jae-in
The Democratic Party's candidate for the presidential primary Moon Jae-in makes a speech at an event to declare their fair contest in the party's presidential primary in Seoul, South Korea, March 14, 2017 REUTERS/Kim Kyung-Hoon