President Donald Trump is paying a courtesy call on his Vietnamese hosts while North Korea's Kim Jong-un was expected to take in some sights on Wednesday before the leaders open their second nuclear summit with a one-on-one meeting and private social dinner.
But the carnival-like atmosphere in the Vietnamese capital, with vendors hawking T-shirts emblazoned with the leaders' faces, stood in contrast to the serious items on their agendas: North Korea's pursuit of nuclear weapons and peace on the Korean Peninsula.
Mr Trump and Mr Kim first met last June in Singapore, a summit that was long on historic pageantry but short on any enforceable agreements for North Korea to give up its nuclear arsenal.
North Korea has spent decades, at great economic sacrifice, building its nuclear programme, and there is widespread scepticism that it will give away that programme cheaply.
Mr Trump has praised Pyongyang for ceasing missile tests and has appeared to ease up on demanding a timeline for disarmament. Mr Trump hopes that Mr Kim, who is seeking relief from crushing US sanctions, will opt to give up his nuclear weapons programme in exchange for help in revitalising his country's economy.
"Vietnam is thriving like few places on Earth. North Korea would be the same, and very quickly, if it would denuclearise," Mr Trump tweeted on Wednesday, hours before he and Mr Kim were due to meet again. "The potential is AWESOME, a great opportunity, like almost none other in history, for my friend Kim Jong-un. We will know fairly soon – Very Interesting."
Mr Trump had a full day of meetings with Vietnamese officials before the one-on-one sit-down and dinner with Mr Kim later on Wednesday. The Korean leader was expected to leave his locked-down hotel to visit various sites in Hanoi.
Mr Trump remains eager to claim an attention-grabbing victory to offset the political turmoil he faces at home.
With the president outside the US, his now-disbarred former personal lawyer was testifying publicly on Capitol Hill later on Wednesday about alleged misconduct by Mr Trump. The Democratic-led House, with backing from several Republicans, approved legislation aimed at blocking the Republican president from steering billions of dollars to build barriers along the US-Mexico border. A House committee also voted to subpoena administration officials over family separations at the border.
Michael Cohen, once Mr Trump's loyal attorney and fixer, has turned on his former boss and co-operated with special counsel Robert Mueller, who is looking into whether the Trump presidential campaign co-ordinated with Russia and whether the president tried to obstruct the investigation.
The president's eldest son, Donald Trump Jr, accused Democrats in Congress of scheduling Mr Cohen's testimony to overshadow the summit.
"After 60 years of failed attempts trying to end the war, trying to end nuclear proliferation on the Korean peninsula, you have finally a president who's willing to do it," he told Fox News Channel. "For the Democrats to try to counter programme that kind of progress – to try to perhaps somehow distract him with this nonsense ... it just goes to show you how much those Democrats really disdain Trump but also America."
The president jabbed at Democrats too, saying in a tweet that they "should stop talking about what I should do with North Korea and ask themselves instead why they didn't do 'it' during eight years of the Obama administration?"