China has responded positively to the developments, as one would expect.
But Wang issued a word of caution, noting that breakthroughs on the North Korean nuclear issue had collapsed in the past.
A quick recap on what's taken place so far this year: North Korean leader Kim Jong-un signaled a willingness to participate in the PyeongChang Winter Olympics in South Korea during his New Year's address.
On Tuesday, South Korean officials said the two Koreas agreed to hold a summit at the truce village of Panmunjeom in late April, with the North voicing readiness to talk with the United States about denuclearization and normalization of bilateral ties.
South Korea has said the North has indicated it is prepared to give up its nuclear weapons programme - a defining feature of its politics for decades - if the USA agrees to guarantee its security. "China will take necessary measures in the event of a trade war".
China's "dual freeze" proposal, unveiled a year ago during Wang's press conference, involves halting both nuclear and missiles tests in exchange for the suspension of U.S.
North Korea and the United States reached a framework agreement in Geneva in 1994 to freeze construction of the North's nuclear reactors, but that accord unravelled in 2003.
The relationship between Seoul and Pyongyang has been ostensibly improving after North Korea chose to join the February 9-25 Olympics in South Korea.
The easing in the Korean Peninsula conflict shows that China's "suspension-for-suspension" plan has worked, Yi said.
"Despite the light at the end of the tunnel the journey ahead will not be smooth", he stressed. It's possible that Wang was making a very oblique reference to this line of thinking in his warning about the potential for insincerity or "disturbance" (also translatable as "interference").
"All must demonstrate political courage and make political decision".
Those visits and meetings that "go a long way toward deepening the world's understanding of China, enhancing China's profile and influence, and facilitating the solution of many global problems", he said.