"Happy to see FM Ri again for a quick meeting here in MFA, just four days after he kindly hosted me in Pyongyang!" Balakrishnan wrote on Facebook.
The Singaporean foreign minister also published photos depicting him and Ri greeting each other and shaking each other’s hands.
Earlier in the day, US President Donald Trump and Singaporean Prime Minister Lee Hsien Long met privately at the Istana, the prime minister's office, and residence, for one-on-one talks ahead of the upcoming summit
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Balakrishnan finished his first trip to Pyongyang on Saturday. After the visit, the diplomat praised the welcoming atmosphere and friendly talks with Ri and President of the Presidium of North Korea's Supreme People's Assembly Kim Yong Nam.
Both Trump and Kim arrived in Singapore on Sunday. The two leaders met with Balakrishnan upon their arrival.