"The DPRK leadership must return to full compliance with its international obligations and to the path of denuclearisation," said Guterres in a statement.
The UN Security Council will meet behind closed doors later Monday to discuss the missile test, the first carried out by Pyongyang since US President Donald Trump took office.
Guterres appealed "to the international community to continue to address this situation in a united manner," in an apparent reference to the United States and China, Pyongyang's ally.
The United States, Japan and South Korea requested the urgent council consultations after North Korea confirmed on Sunday that it had "successfully" tested a ballistic missile.
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North Korea's state-run KCNA news agency said a "surface-to-surface medium long-range ballistic missile" was "successfully test-fired", describing it as a "Korean-style new type strategic weapon system."
The missile flew about 500 kilometers (310 miles) before falling into the sea, South Korea's defense ministry said.
"I would certainly hope that the Security Council would come up with a clear and strong message," Japan's Ambassador Koro Bessho told reporters ahead of the meeting.
North Korea is barred under UN resolutions from any use of ballistic missile and nuclear technology.
The UN Security Council has imposed six sets of sanctions since Pyongyang's first nuclear test in 2006.
The latest round of sanctions imposed in November includes a cap on Pyongyang's coal exports to China, aimed at depriving the communist state of hundreds of millions of dollars in revenue.