Cohen "did bad things unrelated to Trump. He is lying in order to reduce his prison time," the president tweeted from Hanoi, shortly before his sitdown with the North Korean leader.
ADVERTISEMENTHANOI, Vietnam — President Donald Trump broke bread with his "friend" Kim Jong Un here Wednesday night to open their second nuclear summit just hours before former Trump attorney Michael Cohen was due to deliver a damning account of the president's business and campaign practices in an open congressional hearing half a world away.
During meetings with Vietnamese officials earlier in the day, Trump said he was optimistic that he and Kim, the North Korean leader, would be able to strike a deal.
"I look forward to the meeting tonight with Chairman Kim and hopefully it's going to be successful," Trump said. "We'll see what happens but he wants to do something great, and also and I think he wants to ... make North Korea into a great economic power."
Trump's focus was divided between the tasks at hand and politics back at home.
After Cohen's opening statement was published, Trump attacked him on Twitter, accusing his former aide of "lying in order to reduce his prison time."
He also used the social media platform to insult Sen. Richard Blumenthal, D-Conn., a favorite target, for having said in the past that he served in Vietnam when his wartime duty was in the U.S.
"I have now spent more time in Vietnam than Da Nang Dick Blumenthal, the third rate Senator from Connecticut (how is Connecticut doing?)" Trump tweeted. "His war stories of his heroism in Vietnam were a total fraud — he was never even there. We talked about it today with Vietnamese leaders!"
But Trump's main mission here is to get Kim to give up his nuclear weapons. An administration official insisted to NBC News that Trump was "100 percent dialed in" for his meeting with Kim Wednesday.
His strategy relies on the conclusion that Kim will ultimately choose to disarm in exchange for relief from crippling sanctions and the promise of prosperity for his nation.
"Vietnam is thriving like few places on earth. North Korea would be the same, and very quickly, if it would denuclearize," he wrote on Twitter. "The potential is AWESOME, a great opportunity, like almost none other in history, for my friend Kim Jong Un."
But foreign policy experts in Washington worry that Trump's appetite for announcing a deal could lead him to give away too much without getting a firm commitment from Kim to identify and remove his weapons.
"The administration should make clear to Pyongyang that the only way we will dismantle the U.S. and international sanctions regime is when Pyongyang completely dismantles every single nut and bolt of its illicit weapons programs — not a minute earlier," Sen. Cory Gardner, R-Colo., the chairman of the Senate Foreign Relations subcommittee that deals with North Korea, told NBC before the summit.
Trump was expected to be flanked at the dinner at the Sofitel Legend Metropole Hotel here by Secretary of State Mike Pompeo and White House budget director Mick Mulvaney.