Samsung Electronics accounts for a quarter of Vietnam's exports, and the Southeast Asian country is South Korea's third-biggest export market, and the fifth-biggest source of South Korea's imports.

Samsung Display, a supplier for Samsung Electronics and Apple, had earlier asked Vietnam to exempt 700 engineers quarantine, saying they need to prepare for the production of screens for new smartphones, a person familiar with the matter told Reuters this week.

South Korea has Asia's second-biggest coronavirus outbreak outside China, with 7,979 cases as of Friday, and Vietnam, which has just 44 cases, tightened up entry regulations for South Koreans, including making them undergo quarantine.

But despite the controls, a chartered Asiana Airlines plane carrying 186 Samsung Display engineers flew from South Korea to Vietnam on Friday, an Asiana spokesman said.

Samsung Display declined to comment.

Vietnam's foreign ministry representatives were not immediately available for comment.

The airline spokesman said more flights were scheduled to take more Samsung Display engineers to Vietnam but did not provide details.

(Reporting by Heekyong Yang, Additional reporting by Khanh Vu in Hanoi; Writing by Joyce Lee)