President Trump became the first U.S. president to step into North Korea, reaching across the demarcation line to shake hands with North Korean leader Kim Jong Un and stepping across the border, at Kim’s invitation. The president called the moment a “great honor,” and later held a bilateral meeting with Kim at a nearby building in South Korea. Trump said they agreed to form teams to restart negotiations for a comprehensive agreement. Earlier this weekend, Trump sat down with President Xi Jinping of China at the G-20 summit, and both leaders appeared to strike a diplomatic tone in their remarks. ABC's Lana Zak is at the White House and joins Tony with reaction.