A senior South Korean diplomat on Thursday made a thinly veiled criticism of Tokyo's recent restrictions on exports to South Korea, saying any "unilateral" measure out of sync with international norms can't be justified.

Lim Sung-nam, Seoul's ambassador to the Association of Southeast Asian Nations (ASEAN), made the remarks amid heightened tensions over the measure, which Seoul sees as retaliation for last year's Supreme Court rulings against Japanese firms over wartime forced labor.

"Any unilateral measures adopted by WTO members not in sync with international norms, including WTO Agreements, cannot and should never be justified," Lim said during an international forum in Odawara, Japan, according to the foreign ministry. WTO is the acronym for the World Trade Organization.

Lim also called attention to the public statement from last year's summit involving the leaders of the 10-member ASEAN, South Korea, China and Japan, which underscored their commitment to "uphold a global trade environment that is open, mutually beneficial, rules-based and inclusive."

The ambassador, moreover, cited the statement adopted at the close of the Group of 20 summit in Osaka, Japan, last month, which stressed the importance of a "free, fair, non-discriminatory, transparent, predictable and stable trade and investment environment."

Last Thursday, Tokyo enforced toughened restrictions on exports to South Korea in an apparent retaliatory move against last year's Supreme Court rulings here that ordered Japanese firms to compensate South Korean victims of wartime forced labor.

Tokyo has pressured Seoul to step in to address renewed tensions from the rulings as it argues that all reparation issues stemming from its 1910-45 colonization of the peninsula were settled under a 1965 state-to-state accord aimed at normalizing bilateral ties.

But Seoul has refused to intervene in civil litigation, saying it honors court decisions under a democratic constitutional principle that guarantees the separation of the executive, legislative and judicial powers. (Yonhap)