Calls in South Korea for a boycott of Japanese goods in response to Japanese restrictions on the export of high-tech material to the country picked up on Monday as a dispute over compensation for forced wartime labor roils ties between the U.S. allies.

The dispute is the latest flashpoint in a relationship long overshadowed by South Korean resentment of Japan's 1910-45 occupation of the Korean peninsula, in particular with regards to "comfort women," a euphemism for women who provided sex — including those who did so against their will — for Japanese troops before and during World War II.

The latest bitterness over forced labor could disrupt global supplies of memory chips and smartphones. Samsung Electronics Co. and SK Hynix Inc. — the world's top memory chipmakers, and suppliers to Apple and China's Huawei Technologies — could face delays.