US President Donald Trump used the minutes waiting for Kim Jong-un to arrive for their historic meeting to tweet out news that financial analyst and adviser Larry Kudlow has suffered a heart attack.
"Our Great Larry Kudlow, who has been working so hard on trade and the economy, has just suffered a heart attack. He is now in Walter Reed Medical Center," Mr Trump tweeted.
The tweet came after Mr Trump's motorcade arrived at the resort island of Sentosa, about 25 minutes before his meeting with Mr Kim.
Mr Trump began tweeting shortly after his motorcade started moving, but it was the Supreme Court in the US that was on his mind, not the summit.
"Just won big Supreme Court decision on Voting! Great News!" he tweeted.
The multitasking tweets are bound to bring attention to comments Mr Trump made to reporters at the White House last week.
"I don't think I have to prepare very much," Mr Trump said about the summit.
"It's about attitude, it's about willingness to get things done."