Vietnamese President Truong Tan Sang has offered condolences to his South Korean counterpart Park Geun-hye over the ferry sinking incident off South Korean coast.

State-run radio VOV reported on Friday that on hearing that the incident which occurred on Wednesday in waters off South Korea caused death and missing among passengers, Vietnamese president on Thursday expressed sorrow over phone to the South Korean president.

On the same day, Vietnamese Deputy Prime Minister and Foreign Minister Pham Binh Minh also sent sympathies to South Korean Foreign Minister Yun Byung-se.

Asked for Vietnam's response over the ferry incident in South Korea, Vietnam's Ministry of Foreign Affairs (MoFA) Spokesperson Le Hai Binh said at a regular press briefing in capital Hanoi on Thursday that "we are very concerned and worried when learning of the accident in South Korea on Wednesday which has caused many deaths and missing passengers."

"We would like to send our deepest condolences to families of victims and hope that search and rescue efforts by (the) South Korean government will help find the missing passengers soon," MoFA's website statement quoted Binh as saying on Thursday.