Uncertainty over the denuclearization of North Korea is increasing as the deadlock continues in talks with the US. The latest controversy over the North’s missile bases is one more sign that a prolonged tug of war could derail the peace process.

A red light appeared last week when the US and North Korea canceled a meeting in New York between US Secretary of State Mike Pompeo and his North Korean counterpart.

Moreover, US President Donald Trump has reaffirmed that his administration would not rush to negotiate with the North and would maintain the harshest-ever sanctions against the Pyongyang government.

Vice President Mike Pence emphasized this stance in an opinion piece he contributed to the Washington Post. He said the United States would continue to exert unprecedented diplomatic and economic pressure on North Korea.

The US even succeeded in persuading China, the North’s closest ally -- which had previously called for sanctions relief and with which Washington was engaged in a trade war -- not to back down from the sanctions.

After high-level US-China talks in Washington last week, Yang Jiechi, director of the Chinese Communist Party’s Office of Foreign Affairs, said China would “continue to enforce strictly” the relevant UN resolutions.

As if to reciprocate the hard-line US position, North Korea’s state media and its overseas propaganda outlets made it clear that it wouldn’t budge an inch.

A pro-North Korean newspaper in Japan said Saturday that talks between North Korea and the United States would not be necessary if Washington did not intend to implement the June summit agreement between Trump and North Korean leader Kim Jong-un.

What’s noteworthy is that the Choson Sinbo called attention to a recent commentary contributed by a research center chief with the North Korean Foreign Ministry, in which he warned that the North could seriously reconsider its Byungjin policy (of pursuing both economic growth and nuclear weapons development) if Pyongyang’s demand for corresponding steps from Washington were not met.

As the newspaper noted, that was not a statement that a North Korean researcher could write of his own accord. In other words, the North was threatening to revoke its commitment to denuclearization unless the US eased sanctions and guaranteed the regime’s safety.

In contrast to the standoff between the US and the North, inter-Korean peace and reconciliation efforts seem to be in full stride. The two Koreas have already completed the first round of mine-clearing work in the border area and demolished 11 guard posts inside the Demilitarized Zone.

On Monday, the two sides held a meeting on the plan to start construction work to connect cross-border roads and railways before the end of this year.

South Korean Unification Minister Cho Myong-gyon’s current five-day trip to the US is seen as an effort by the Seoul government to fine-tune with Washington some of the inter-Korean peace programs that might interfere with the international sanctions against the regime, including the road and railway connection projects.

But the problem is that the North -- as in the past -- intends to separate inter-Korean relations from denuclearization negotiations with the US.

The latest report from the US think tank the Center for Strategic and International Studies, on the presence of undeclared missile bases in the North, is the latest evidence that Pyongyang still might be pursuing nuclear and missile activities. Both Trump and the South Korean presidential spokesperson played down the CSIS report, but they only fueled the growing skepticism about achieving a full, thoroughly verified denuclearization of the North.

Indeed, what the North has done is -- contrary to its commitments -- merely imposed a moratorium on nuclear and missile tests and destroyed some of its facilities for show.

All these developments lend weight to suspicions that the North might be continuing its nuclear and missile activities and that Trump, as Sen. Edward Markey aptly said, is “getting played by Kim.” It is obvious what the international community, including South Korea, has to do: maintain the sanctions and seek new ways to persuade or pressure the North to take substantial denuclearization steps.