After President Donald Trump took 20 unprecedented steps into North Korea Sunday, reaction quickly poured in from 2020 Democratic hopefuls on the campaign trail.

Here's what some of the candidates are saying:

Sen. Bernie Sanders said he has “no problem” with Trump meeting with Kim Jong-un, but said the issue he took was with Trump’s “incredible inconsistencies.”

“I don’t want it simply to be a photo opportunity, the whole world’s media was attracted there,” Sanders said on ABC's "This Week."

Sen. Amy Klobuchar, appearing on CNN's "State of the Union," said diplomacy is not as easy as bringing a hot dish over the fence to the dictator next store; there needs to be a clear focus and a clear mission and clear goals.

"I don't think we know it works until there is results," Klobuchar told CNN's Brianna Keilar.

The Joe Biden campaign put out a statement, slamming Trump for his relationship with dictators.

“President Trump's coddling of dictators at the expense of American national security and interests is one of the most dangerous ways he's diminishing us on the world stage and subverting our values as a nation. This past week he yet again fawned over Kim Jong-un -- to whom he's made numerous concessions for negligible gain -- joked with Vladimir Putin about our election security and 'getting rid' of journalists, and even expressed sympathy for Turkey buying Russian missiles," the former vice president's spokesman Andrew Bates said in a statement. "His conduct reinforces that we urgently need a president who can restore our standing in the world, heal relationships with key allies Trump has alienated, and deliver real change for the American people."

Sen. Elizabeth Warren tweeted, "Our President shouldn’t be squandering American influence on photo ops and exchanging love letters with a ruthless dictator. Instead, we should be dealing with North Korea through principled diplomacy that promotes US security, defends our allies, and upholds human rights."