Presidential security adviser Kwon Jin-ho says the government tapped all available channels with Washington in its ultimately unsuccessful efforts to secure the release of slain hostage Kim Sun-il in Iraq.

Addressing the parliamentary defense committee Thursday, Kwon said the U.S. ambassador in Seoul had telephoned Korean officials in the early stages of the crisis to assure them that the U.S. would do everything possible to resolve the hostage incident.

After the phone call, Kwon said, there was continued contact between South Korean and American liaison officers.

Asked why the Seoul government was so quick in reconfirming its commitment to sending troops to Iraq, Kwon said that the statement, at that time, was meant to emphasize the peaceful nature of the planned troop deployment.

Iraqi insurgents who kidnapped Kim had given South Korea 24 hours to withdraw its troops from Iraq and cancel its plan to send more troops. He was beheaded not long after the deadline passed.

Some opposition lawmakers criticized the government for being too hasty in reconfirming the troop deployment plan, alleging that it had aggravated the situation and destroyed any hope for the hostage's rescue.