Americans are more optimistic than Japanese that the upcoming U.S.-North Korea summit will help resolve the nuclear standoff on the Korean Peninsula, a survey showed Friday.

Of the American respondents, 21.8 percent said they expect "significant progress" toward denuclearizing the peninsula when U.S. President Donald Trump and North Korean leader Kim Jong Un meet in Singapore on Tuesday, compared with 6.2 percent of Japanese respondents.

The joint survey by Japanese think tank Genron NPO and the University of Maryland also showed that 34.3 percent of Americans believe Trump has agreed to meet Kim because he sees a chance for denuclearization, while 33.7 percent of Japanese said the president wants a foreign policy achievement.

Asked why Kim had agreed to the summit, 37.5 percent of U.S. respondents said Trump's hard-line stance had worked, while in Japan 39.1 percent said it was because of international economic sanctions and pressure from China.

The survey covering 1,215 Americans and 1,000 Japanese was conducted from the middle of May until earlier this month.