Freedom of navigation and flight should be guaranteed in the disputed South China Sea, South Korea's Defense Minister Han Min-koo said in a regional security forum held on Wednesday in Malaysia where defense chiefs from the U.S. and China and Asian countries gathered together.

Speaking to the general session of the ASEAN Defense Ministers' Meeting-Plus (ADMM-Plus), Han said "The stance of the Republic of Korea is that a peaceful resolution of the South China Sea dispute and the freedom of navigation and flight should be guaranteed."

It was the first time a high-ranking South Korean official referred to the South China Sea dispute while the top defense officials of both the U.S. and China sat together.

Han's stress of freedom of navigation, which has often been highlighted by the U.S. in the South China Sea issue, appears to be in harmony with the ally, rather than with China.

"The dispute should be settled peacefully through an agreement among related parties and in accordance with international standards," Han noted.

Regional tensions have grown amid China's ongoing construction of artificial islands, called Spratly, in the South China Sea, seen as a move to bolster its territorial claims in the waters also claimed by the Philippines and Vietnam.

Last week, the U.S. guided missile destroyer USS Lassen sailed close to one of the China-built islands, flaring up tensions between the super powers over the disputed waters.

The defense minister also called for North Korea's denuclearization during the general session address, warning that the country's development of missiles and nuclear weapons is escalating regional tensions.

"The Republic of Korea is combining dialogue and pressure to achieve the denuclearization of North Korea," he said. "North Korea should stick to the United Nations Security Council resolutions and return to the six-party talks to denuclearize in a complete, verifiable and irreversible manner."

The ADMM-Plus kicked off Tuesday for a three-day run in Kuala Lumpur, involving the 10 ASEAN nations plus eight dialogue partners including South Korea, Japan, China Russia and the United States.

Disputes between the United State and China over the South China Sea overshadowed the regional security forum, with the member countries failing to adopt a joint declaration due to the friction.

Member countries of the ADMM-Plus had intended to adopt a joint statement following the general meeting held in Kuala Lumpur earlier in the day, but the efforts fell through after China voiced strong protest, a South Korean official said.

China did not accept the draft of the declaration which mentioned the establishment of a Code of Conduct (COC) of Parties in the South China Sea that will govern the activities of the countries involved in the territorial dispute in the region.

The U.S., meanwhile, insisted the binding COC as well as the Declaration on the Conduct of Parties in the South China Sea, a non-binding document signed by China and the ASEAN countries in 2002, should be laid out in the ADMM-Plus joint declaration, the official noted.

"The Chinese side expressed its rejection under the understanding that the South China Sea issues are basically matters pertaining to diplomatic authorities and this matter should not be reflected on the document of defense authorities' forum," the official added.

As the China-U.S. bickering grew further, ASEAN countries suggested listing the issue in a Chairman's Declaration, but China vetoed it as well.

The U.S.-China rivalry has overrode other issues during the meeting of their defense ministers, Ashton Carter and Chang Wanquan, held on the sidelines on Tuesday, according to sources.

During the meeting, the U.S. side insisted that it will continue operations in the South China Sea while the Chinese side lodged a strong protest against the sailing of the USS Lassen in the area last week.

Meanwhile, following a bilateral meeting with his Chinese counterpart, Han told reporters that he proposed opening one more hotline each for the Navy and the Army of the two countries in a bid to stave off any accidental clash in the sea and air. The response was "positive," he added.

Han said that the Chinese side also requested building a hotline between defense ministries of the two countries "as soon as possible" and invited him to visit China earlier next year. (Yonhap)