"The US has stressed the importance (of its allies' role) and made requests for our participation both directly and indirectly during several meetings," ministry spokesperson Choi Hyun-soo told reporters. "We have been preparing for our contribution, but no decision on how to do that has been made."

Choi said that the government has been mulling various ideas without taking into account Japan's recent decision to deploy self-defense forces there.

Like in other countries, sending troops abroad is a very sensitive issue here. South Korea's security officials have internally discussed options.

Some media here reported that the government is considering expanding South Korea's military role and activity there "in stages."

A possible first step is to dispatch a defense officer to the local combined command led by the US military.

South Korea's anti-piracy Cheonghae Unit is already operating in the Gulf of Aden. Earlier this month, the National Assembly passed a motion to extend its mission, which started in 2009, through Dec. 31, 2020.

Broadening its operational areas to cover the strategically important waters may also be a choice.

Cheong Wa Dae officials have also reiterated that no decision has been made yet. They have been cautious and prudent about mentioning the matter in public.

What's noteworthy is that Cheong Wa Dae has included the issue in its press briefing on the NSC meeting.

It came as Seoul is in tough negotiations with Washington on splitting the financial burden for the presence of the 28,500-strong US Forces Korea.

The US is demanding South Korea pay far more, reportedly a fivefold hike from this year's share of $870 million.

South Korea has emphasized its commitment to playing a bigger role in handling not only regional security problems but also global affairs.

Officials here pointed out Seoul is spending a lot of money and making other efforts, either calculable or not, for the further development of the time-honored alliance.

Cheong Wa Dae may be trying to remind US officials of South Korea's seriousness in its commitment as a key ally, while the Strait of Hormuz issue is not directly related to the defense cost talks.

Critics say it's unconstitutional to send troops to the strait.

"Participation in military action in the Strait of Hormuz is an act that will irritate Iran and increasingly fan conflicts," Rep. Kim Jong-dae of the progressive opposition Justice Party said.

South Korea should rather clarify its support for a diplomatic resolution to the security problem, he added. (Yonhap)