Japan's Foreign Ministry on Friday raised its travel alert for the Thailand-Cambodia border area following recent armed clashes between the two Southeast Asian countries, advising citizens not to visit the region.

Under the updated travel advisory, the designated area has been placed under a level 3 alert, the second-highest on the four-point scale, urging nationals to "avoid all travel."

The clashes broke out on Thursday with Thai authorities saying more than a dozen people, including civilians, have been killed.

On Friday, Japanese Foreign Minister Takeshi Iwaya told his Cambodian counterpart Prak Sokhonn that the tensions should be eased "peacefully through dialogue," expressing Tokyo's "deep concern" during their phone talks, his ministry said.