United States President Donald Trump has expressed hope for positive results in his upcoming meeting with North Korean leader Kim Jong-un.

Trump tweeted Sunday morning Korea time that he is on his way to Singapore where they have a chance to achieve a truly wonderful result for North Korea and the world.

He added that it will certainly be an exciting day and Kim will work very hard to do something that has rarely been done before.

During a press conference on Saturday local time after the G7 summit in Canada, Trump also cast his Tuesday summit with Kim as a "onetime shot" for him to give up his nuclear weapons and make his country "great."

The U.S. president said that he was embarking on a "mission of peace," adding the summit with Kim is unknown territory but he really feels confident Kim wants to do something great for his people.