President Donald Trump says Vietnam, the site of his second round of nuclear talks with Kim Jong Un, is thriving economically and that North Korea could, too, if it would give up its pursuit of nuclear weapons.

Before sitting down with Kim later Wednesday in Hanoi, Trump tweeted that "North Korea would be the same, and very quickly, if it would denuclearize. The potential is AWESOME, a great opportunity, like almost none other in history, for my friend Kim Jong Un."

In a second tweet, Trump took a shot at Democrats in Washington, saying they should stop telling him what to do with North Korea and "ask themselves instead why they didn't do 'it' during eight years of the Obama Administration?"

Trump faults previous administrations for inaction on North Korea.