Editor's note: Tom Fowdy, who graduated from Oxford University's China Studies Program and majored in politics at the Durham University, writes about international relations focusing on China and the Democratic People's Republic of Korea. The article reflects the author's views, and not necessarily those of CGTN.

On Tuesday morning DPRK leader Kim Jong Un's official train arrived in Vietnam following a two-day-long journey from Pyongyang. He will meet U.S. President Donald Trump on Wednesday..

While it should be clear that this event is strictly an engagement between the DPRK and the United States, something China is very careful not to intrude upon, this does not mean that it does not have a role to play.

Instead of sitting on the sidelines, Beijing's influence remains crucial in moving forward on any agreement which may emerge.

Taking a cautious and pragmatic approach, Beijing will ensure that Washington's goals are not entirely centered on sanctions. At the same time, it is crucial to provide Kim Jong Un with options to consider to buffer his own interests in future negotiations with the United States.

Although China's considerations and methods concerning the DPRK may differ from those of the United States, it is important not to underestimate Beijing's fundamental interest in promoting Pyongyang's denuclearization process.

Several analysts have repeatedly accused China of deliberately ignoring or skirting United Nations sanctions concerning the DPRK over the years.

Although there is little evidence to support such a claim, it is fair to say that, fearing regional instability and pushing the country towards collapse, China has been wary of placing serious and sustained pressure on DPRK.

Rather than dismissing sanctions entirely, it has adjusted its scope in accordance with its neighbors' behavior and the fundamental attitude of the United States towards it. From 2016, China's stance on DPRK largely switched from flexibility to growing assertiveness, with a scathing Xinhua editorial stating, "A nuclear DPRK has no future."

By 2017, the situation became untenable. Upholding the norms of non-proliferation, China may have held back on America's more brutal demands, such as a request for a total fuel embargo. Nevertheless, it was serious in fulfilling UN resolutions with the view of putting pressure on DPRK to negotiate its rapidly advancing nuclear program.

These events led to a drift between the two nations. Its annual trade and commerce with DPRK plummeted, though the relationship would later rekindle.

By 2019, tensions eased and a diplomatic process is well underway. Chinese President Xi Jinping and DPRK leader Kim Jong Un have met on numerous occasions.

However, China has not re-visited the question of sanctions on DPRK. There are some anecdotal signs that some smaller measures have been enacted, however, most data and signs at the border indicate that major commerce, such as mineral imports from DPRK, have not resumed.

Beijing understands and respects that concessions cannot be granted unless the DPRK agrees to make meaningful progress on denuclearization.

It would not be in China's interest to violate those boundaries, not in terms of regional stability nor in terms of its own relationship with the United States, which is experiencing its own difficulties.

In view of this, China will carefully follow the upcoming summit in Hanoi. In the aftermath, it may offer DPRK its own economic incentives and sanction relief.

At the same time, however, continued diplomatic support from China to the DPRK will continue and ultimately in the view of concessions, enhance. As much as China desires Pyongyang's denuclearization, it is much less dogmatic than the United States in how they achieve such results.

This allows Kim to tread carefully with Washington in negotiations, buffering him against more unilateral and unrealistic demands. Beijing will also offer support to Seoul, giving its blessing to inter-Korean engagement, to the resumption of inter-Korean projects and Moon Jae-in 's other objectives.

All in all, rather than being a nuisance, China's role in the outcome of the summit is one that will add flexibility, stability and balance to the outcome.

Far from being an obstacle, Beijing has in fact been able to facilitate both the desires of Pyongyang and the United States throughout this entire saga. Rather than enabling the DPRK's nuclear ambitions, it has drawn clear red-lines, enforced them and pushed Kim to negotiate.

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