Americans are more optimistic than the Japanese that an upcoming U.S.-North Korea summit will help to 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 the denuclearization of the peninsula in the meeting between U.S. President Donald Trump and North Korean leader Kim Jong Un in Singapore on Tuesday, compared with 6.2 percent among Japanese respondents.

The joint survey by Japanese think tank Genron NPO and the University of Maryland also showed 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 Chinese pressure on North Korea.

The survey covering 1,215 Americans and 1,000 Japanese was conducetd between mid-May and early June.