South Korea said Wednesday it will file a complaint to the World Trade Organization over Japan's "politically motivated" export restrictions, upping the ante in an intensifying dispute with the neighbor. 

Seoul and Tokyo have been embroiled in the trade and diplomatic spat since Tokyo tightened export controls in early July on three chemicals essential to making memory chips and high-spec displays, key products of South Korean companies such as Samsung and LG. 

The restrictions follow a series of South Korean court rulings ordering Japanese firms to pay for forced labor during World War II. 

The ongoing dispute has also seen the two neighbors remove each other from their "white lists" of trusted trading partners and prompted South Korea not to renew a military intelligence sharing pact.

"Japan's export curbs on three items are driven by political motivations linked to a Supreme Court ruling over the issue of forced labor," said Trade Minister Yoo Myung-hee at a press conference.  

"Targeting South Korea is … in violation of WTO's principles banning discriminatory practices."

With South Korea's role as a main supplier of memory chips and displays, she said, the curbs have caused "significant uncertainty" in the global economy.

Yoo said South Korea will request a bilateral consultation at the WTO as a first step to resolve the issue.