Around 40 percent of Taiwanese believe Japan would dispatch troops to help defend Taiwan if China invaded the self-ruled island, more than those who think the United States would come to their assistance, according to a survey released Tuesday.

The two-day survey conducted from March 14 by the Taiwanese Public Opinion Foundation found that 43 percent of the respondents believe Japan would come to Taiwan's aid militarily should China attack, while those who said the United States would dispatch troops to the island came to 35 percent.

Shiyu, or Lion Islet, part of Kinmen County, one of Taiwan's offshore islands, is seen in front of the Chinese city of Xiamen, China, on April 20, 2018 in Kinmen, Taiwan. (Getty/Kyodo)

You Ying-lung, chairman of the foundation, a private think tank, attributed the significant shift in public opinion to the "effect of the Ukraine situation," saying the conflict between Ukraine and Russia has had an immense impact on the Taiwanese public.

Russia's invasion of Ukraine, which began in late February, has sparked an international outcry, with the United States engaged in the unfolding conflict in Ukraine.

In the previous survey in November, 58 percent of those polled said they thought Japan would dispatch troops for Taiwan's defense, while 65 percent believed the U.S. military would assist Taiwan in the event of a China invasion.

Taiwan and mainland China have been separately governed since they split as a result of a civil war in 1949. China regards Taiwan as a renegade province awaiting to be united by force if necessary.

The survey, conducted among a random sample of 1,077 adults from around the island by phone, had a margin of error of plus or minus 2.99 percentage points with a 95 percent confidence interval.