NATO's Secretary General is in Seoul for a three day trip.
North Korea-related issues are high on the agenda.
Jens Stoltenberg met with foreign minister Kang Kyung-wha and stressed the importance of cooperation in tackling Pyongyang's nuclear threats.
"We are certainly very, very grateful for NATO's strong support in the face of these provocations, there has been a number of statements coming out of NATO against these provocations and we need that support from the international community."
"It's a big challenge for the Republic of Korea being so close, but it is also a challenge for the rest of the world, because North Korea is now developing more longer range missiles."
The duo reportedly discussed other global threats as well, such as terrorism and cybersecurity.
They also signed a partnership agreement renewing Korea's relationship with NATO.
The Secretary General is scheduled to meet with President Moon Jae-in on Thursday.