President Moon Jae-in departed for New York on Monday with a heavy burden on his shoulders to attend the UN General Assembly. The burden is attributable to the tense and grave security situation caused by North Korea’s nuclear and missile provocations.

He is to deliver a keynote address at the UN General Assembly on Sept. 21 and then hold a three-way summit with US President Donald Trump and Japanese Prime Minister Shinzo Abe in New York.

The three leaders are expected to discuss whether to impose additional sanctions against the North for its latest launch of a ballistic missile.

Moon needs to clear suspicion from the US and Japan about South Korea’s policy to offer humanitarian assistance to the North at the request of UN agencies.

Without a doubt, he should strengthen cooperation with the European Union which resolved to toughen its sanctions against Pyongyang.

His message at the UN General Assembly must be a matter of the utmost concern to its members expecting solutions from the head of a country under direct threat from North Korea. His keynote speech amounts to a declaration of South Korea’s basic position on the North to the international community.

He needs to stand firm on UN sanctions against Pyongyang for deriding the international community by firing an intermediate range ballistic missile just three days after the UN Security Council adopted Resolution 2375 for its sixth and strongest ‘hydrogen’ bomb test.

By all means, Pyongyang will never stop developing intercontinental ballistic missiles further and trying to deploy IRBMs for actual warfare.

The North is talking big in front of the international community. The communist state says it won’t to listen to it until it is recognized as a nuclear power and as such sits at the negotiating table with the US on the same footing.

The problem is the absence of proper means to foil the wayward communist state’s nuclear and missile tests right away. Still, Moon must urge UN members, including China and Russia, to implement sanctions faithfully such as restrictions on oil supply and North Korean labor employment.

The pressing need of the hour is to cut off the sources of funds raised by the North to develop nukes and missiles. It reportedly earns much of the funds through illicit arms exports, remittances from overseas laborers, counterfeit bills and cybercrimes such as hacking banks’ networks.

Moon must call on the international community to work together to keep the North from doing illegal trade with its members. Close cooperation and coordination is a prerequisite to isolate the North and wither its nukes and missile program.

Above all, watertight cooperation with the US is crucial to stop the runaway North Korean regime from completing its nuclear missiles. In that sense, it was timely and appropriate that Moon and Trump had a telephone conversation a day before his departure and agreed to beef up the Korea-US alliance.

Now is time for Moon to show the international community his unyielding determination to pressure the North.

However, his administration’s policy to provide humanitarian assistance to the North arouses doubt about his will.

The Ministry of Unification said on Sunday that humanitarian aid to the North will be pushed independently of political situations and that it does not violate sanctions and pressure, either.

This stand runs the risk of backing up China and Russia’s negative views of tighter sanctions such as a total ban on oil supply. They cite that such tougher sanctions will only cause humanitarian distress.

There would be no use pressuring the North if one side raises the pressure while the other side reduces it.

It is about time all sides put stronger pressure on the North. When it comes to aid to the North, a prudent approach is needed. Its timing should be determined depending on the political and security situations.

The South cannot persuade the international community to put airtight pressure on the North if it is seen as helping it withstand the pressure.