The family have urged the South Korean government to act

The 33-year-old had been in Iraq for just over a year, and was planning to return home in July for his father's 70th birthday.

His distraught family urged Seoul to put their son before troop deployments.

"The government should do what it can to save my son's life. Time is running out," his mother Shin Young-ja pleaded.

She said she last heard from her son in April when he reassured her he was safe and well.

"Don't worry about me, mum. I feel comfortable," he reportedly told her.

Arabic degree

Kim, from the southern port city of Busan, graduated with an Arabic degree from Hankuk University of Foreign Studies in February 2003.

He arrived in Iraq in June 2003 and was working for South Korean firm Gana General Trading, which supplies goods to US troops, at the time of his capture.

The deadline expires at sunset on Monday

Shin Young-ja told Yonhap news agency her son's life should come before any plan to send troops.

"I used to think in the past the troop dispatch had to take place even when my son was in Iraq, but now, in such a situation, I think my son must be saved first," she said.

"He is introverted, kind-hearted and studies hard," she told South Korea's YTN television.

His tearful younger sister Kim Jung-sook also appealed for his safe return.

"Please return my brother to us so that he can be with us for daddy's 70th birthday anniversary next month," she said.

His father, Kim Jong-kyu, said through sobs on YTN: "He should be released through negotiation. He should be saved. My life is over without him."

Plea

A terrified Kim had been shown on video footage flanked by three masked Iraqi militants, who warned he would be killed unless South Korea pulled out its troops.

Kim was heard to plead in English: "Korean soldiers, get out of here. I don't want to die. I don't want to die."

The South Korean government said it will do its utmost to secure Kim's release, but has refused to comply with the hostage-takers' demands.

Plans to send a further 3,000 troops to Iraq starting in August will also still go ahead, said the government.