South Korea on Friday voiced "deep regrets" over recent attacks on Saudi Arabia by Yemen's Houthi rebels, reiterating any assault on civilians should not be tolerated.

On Monday and Tuesday, Houthi rebels launched drone and ballistic missile attacks on several densely populated areas in Saudi Arabia, ratcheting up tensions in the conflict-laden Middle East.

"The government expresses deep concerns about the drone and missile attacks targeting civilian areas, and reaffirms that any attack on civilians can't be tolerated under any circumstances," Kim In-chul, spokesman for the foreign ministry, said in a commentary.

Kim added that South Korea supports the ongoing international efforts to bring an end to the civil war in Yemen. (Yonhap)