As I have said before from the Chinese perspective a freeze deal between the US and North Korea is in their interests. Freezing US-ROK joint military exercises is a way to reduce military readiness and push forward the long term goal of separating the ROK from the US:
China reiterated on Thursday that the most reasonable way to resolve North Korea’s nuclear stalemate is to push for a stop to joint military exercises between South Korea and the U.S. in exchange for freezing Pyongyang’s nuclear and missile provocations.
“China sees the freeze-for-freeze scheme is the most reasonable way,” Geng Shuang, China’s foreign ministry spokesman, told a regular press briefing.
He made the remarks in response to what U.S. President Donald Trump earlier said.
Explaining the outcome of his 12-day Asia trip that also included a summit with Chinese leader Xi Jinping, Trump said on Wednesday (Washington time) that the two leaders agreed that they “would not accept” the freeze for freeze agreement, “like those that have consistently failed in the past.”
The spokesman said stopping the joint military exercises and provocations at the same time is the “first step” necessary to create an environment for talks and called for other countries to “actively” consider the method that China had proposed. [Yonhap]
You can read more at the link, but the whole dispute over the US deployment of the THAAD battery to South Korea is just another front in China’s long term effort to separate the US and the ROK.