Political flare-ups in Asia are putting the brakes on Fast Retailing Co.'s overseas momentum, as the Uniqlo operator reported the worst decline in its quarterly revenue in a decade for its international segment.

Asia's largest retailer has long counted on overseas expansion to power growth in the face of a weak Japanese market. Now that strategy has come up against the political protests in Hong Kong as well as the trade dispute between Japan and South Korea.

Fast Retailing on Thursday reported a 3.6 percent drop in first-quarter sales for Uniqlo's international segment, citing "significant declines" in those two trouble spots. Except for a minuscule decrease of 0.2 percent in 2017, it's the first quarterly drop for the segment in 10 years, according to Bloomberg data. Operating profit for the international business fell 28 percent, for the first quarterly earnings decline since 2016.