(CNN) A letter from US President Donald Trump to North Korean leader Kim Jong Un was given Saturday to North Korea's foreign minister at the Association of Southeast Asian Nations (ASEAN) meeting, US Secretary of State Mike Pompeo tweeted.

I had the chance to speak with my #DPRK counterpart FM Ri Yong Ho @asean today. We had a quick, polite exchange. Our US delegation also had the opportunity to deliver @Potus reply to Chairman Kim's letter. pic.twitter.com/1DiR6UDj4Q — Secretary Pompeo (@SecPompeo) August 4, 2018

Trump's letter comes in response to a letter he received this week from Kim, according to State Department spokeswoman Heather Nauert. The letter from the President was delivered to North Korean Foreign Minister Ri Yong Ho after Pompeo shook hands and spoke with Ri at the ASEAN meeting in Singapore, Nauert said.

US Ambassador to the Philippines Sung Kim handed the Trump letter to Ri, and Ri thanked him, Nauert said. Sung Kim was previously an ambassador to South Korea and a special representative for North Korea policy.

While attending the ASEAN meeting Saturday, Pompeo and Ri approached each other and Pompeo told Ri they should talk again soon, according to an account from Nauert. She said Ri replied, "There are many productive conversations to be had."

Asked what the handshake between the two diplomats might represent, Nauert said, "Anytime you have conversations or interactions like that, especially given where our two countries were one year ago, is a step in the right direction."

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