U.S. President Donald Trump said Tuesday that "we're ready to start a new history" following his historic summit with North Korea's Kim Jong Un in Singapore. "Anyone can make war, but only the most courageous can make peace," he said.

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Trump hailed the "new chapter" in U.S.-North Korea relations and called his talks with Kim "honest, direct and productive," saying that "we got to know each other well in a confined period of time under very strong circumstances."

Trump said that he will speak to South Korean President Moon Jae-in after his press conference, while thanking Japanese Prime Minister Shinzo Abe and China's Xi Jinping.

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He added that sanctions will remain in effect and that North Korea has agreed to destroy a major missile testing site, which was not part of the joint statement. He added that sanctions will be lifted "once we can be sure the nukes are no longer a factor." Trump said he halted plans last week for 300 new sanctions designations against North Korea because it would be "disrespectful."

When confronted with questions about North Korea's human rights record, Trump said he "knows how to run it tough" and that "I didn't say [KIm] was nice." He noted that without Otto Warmbier, the American hostage who died after returning home in a coma, "this wouldn't happen. Something happened that day." He said he discussed human rights with Kim and will hold more conversations on the matter in the future.

Trump said the U.S. "will be stopping the war games" with South Korea and "I want to get out soldiers out, I want to get our soldiers back home," though he noted that "that's not part of the equation right now."

"We fly in bombers from Guam. Oh great, nearby. Six-and-a-half hours. That's a long time for these big massive planes to be flying to South Korea to practice and drop bombs all over the place and then go back to Guam. I know a lot about planes, and it's very expensive," Trump said.

Referring to North Korea's commitment to denuclearization, Trump said that once the process is started, "it's pretty much over." When asked why he couldn't get Kim to agree to complete and irreversible denuclearization, he said that "I'm here for one day. The process is now going to take place." He also termed North Korea's nuclear arsenal as "substantial."

He added that Secretary of State Mike Pompeo and National Security Adviser John Bolton will meet with North Korea to continue discussing denuclearization, saying "we're getting together next week to go over the details."

He confirmed that he will go to North Korea "at the appropriate time" while repeating that he will invite Kim to the White House.

Trump also referred to Iran, saying the Islamic Republic is a different country than it was a few months ago and is less confident in Syria and other places after nixing the nuclear deal. He called the sanctions against Iran "brutal."

Trump, however, criticized the nations in the Group of Seven, claiming the U.S. is "being taken advantage of" by virtually every member. He said Canadian Prime Minister "learned" from the mistake of criticizing him, adding that it's going to cost Canada "a lot of money."