A boy checks the damage to a building hit in an Israeli airstrike in the southern village of Akbieh, Lebanon, Tuesday. (AP-Yonhap)

South Korea is reviewing an emergency evacuation plan to ensure the safety of South Korean citizens in the Middle East as the region on Monday suffered the deadliest conflict in almost two decades with Israel's airstrike in Lebanon targeting Iran-backed militant group Hezbollah.

The measure was discussed at the emergency meeting on Tuesday to monitor the situation in the Middle East in terms of national security and economy, presided over by President Yoon Suk Yeol's aides, National Security Adviser Shin Won-sik and Director of National Policy Sung Tae-yoon.

A source from the presidential office who attended the meeting told The Korea Herald the evacuation could be in effect not only in Lebanon, but also in Israel and Iran if under extreme circumstances.

The number of South Korean nationals residing in Lebanon, Israel and Iran are estimated at around 140, 480 and 100, respectively.

Also on Tuesday, First Vice Minister Kim Hong-kyun said in a televised interview with Channel A that Seoul "is bracing for the regional escalation of the war situation," but asked Korean nationals to "leave the country (in the Middle East) immediately" before flights from the Middle East countries are canceled.

Earlier in July and August, Yoon's office held three rounds of meetings to monitor the Middle East situation, repeatedly recommending Korean nationals' departure from the region.