The foreign ministers of North Korea and South Korea spoke face-to-face at a gala in Manila Sunday night, according to South Korean media reports, at a time of heightened tensions over Pyongyang’s missile program.

South Korea’s Kang Kyung-wha exchanged words with her North Korean counterpart Ri Yong Ho ahead of the ASEAN Regional Forum, according to South Korean news agency Yonhap and broadcaster YTN.

The annual security dialogue draws in 27 countries, including North and South Korea, the United States, China and Russia.

It was the first high-level encounter between the two Koreas since South Korea President Moon Jae-in took office in May and comes after the United Nations Saturday approved the “strongest sanctions ever imposed” in response to North Korea’s missile testing.

Moon has long been a proponent of greater dialogue with Pyongyang in order to diffuse tensions on the Korean Peninsula.

As an aide to President Roh Moo-hyun, Moon helped craft the so-called “Sunshine Policy,” which called for an increase of engagement in the political and economic spheres.

In July, South Korea’s Defense Ministry proposed talks between representatives of the two countries’ militaries at Tongil-gak on the North Korean side of Panmunjom, the so-called truce village in the Demilitarized Zone (DMZ) that separates the two rivals.

North Korea has yet to respond to the overtures.

“Ultimately, President Moon Jae-in is a strong believer on dialogue and wants to get things on a different track with North Korea,” said John Delury, an associate professor at Yonsei University’s Graduate School of international Studies in Seoul.

According to South Korean news agency Yonhap, citing an unnamed government source, Ri told Kang during their meeting Sunday that South Korea’s offer of talks “lacked sincerity.”

At the same forum a year ago, South Korea’s former foreign minister Yun Byung-se also talked briefly with Ri.

U.S. Secretary of State Rex Tillerson, who is attending the forum, skipped the gala dinner where the two ministers spoke but is expected along with the 24 other top diplomats from region to be in the same room as North Korea’s representative at a session later Monday.

However, they’re not expected to meet one-on-one.

Read more: CNN