President Trump announced from Singapore on Tuesday that his top economic adviser, Larry Kudlow, was hospitalized outside Washington, D.C., after suffering a heart attack.

"Our Great Larry Kudlow, who has been working so hard on trade and the economy, has just suffered a heart attack," Trump tweeted as he arrived at the denuclearization summit with North Korean leader Kim Jong Un.

White House press secretary Sarah Huckabee Sanders later described the heart attack as "very mild" and said Kudlow is expected to make a "full and speedy recovery."

"Larry is currently in good condition at Walter Reed National Military Medical Center and his doctors expect he will make a full and speedy recovery. The president and his administration send their thoughts and prayers to Larry and his family," she said in a statement.

Kudlow, the director of the National Economic Council, joined Trump last weekend during a contentious Group of Seven (G-7) summit of world leaders in Canada. The meeting was clouded by Trump's decision to impose steep steel and aluminum tariffs on U.S. allies and other threats on trade.

After the president left for Singapore, he announced he would not sign on to a carefully crafted joint statement by the group because of anti-tariff comments made by Canadian Prime Minister Justin Trudeau.

Kudlow appeared on CNN's "State of the Union" to support the president and bash Trudeau, whom he accused of "betrayal," saying he "stabbed us in the back."

"He did a great disservice to the whole G-7," he said.

Trump tapped Kudlow, a longtime CNBC commentator, to lead the National Economic Council in March. He replaced Gary Cohn, the former Goldman Sachs president who resigned after disagreeing with Trump's move to impose the tariffs.

Kudlow, who also served in the Reagan administration, holds traditional Republican views on low taxes and fewer regulations and has in the past been resistant to higher trade barriers.

Nonetheless, the 70-year-old adviser has been a constant presence on cable television and radio to defend Trump's economic and trade policies. Kudlow advised Trump during the campaign on an informal basis, helping to draft an initial tax plan in the run-up to the election.

"I've known him a long time," Trump said of Kudlow in March. "We don't agree on everything. In this case I think it's good. I want a diversity of opinion ... He backed me very early in the campaign, I think the earliest. I think he was one of my original backers. He's a very, very talented man."

After working in the Reagan administration, Kudlow studied economics at Princeton University and served as chief economist at Bear Stearns before leaving in the 1990s to treat a substance abuse addiction. He later reemerged as a pundit on cable television.

- Updated at 10:37 p.m. Julia Manchester contributed.