SEOUL - Top diplomats and defense officials from South Korea and the United States on Wednesday warned of "serious consequences" in case of the Democratic People's Republic of Korea (DPRK)'s further provocations and announced a plan to introduce fresh sanctions against the DPRK's proliferation activities.

US Secretary of Defense Robert Gates and US Secretary of State Hillary Clinton hold a joint news conference with South Korean Foreign Minister Yu Myung-hwan and South Korean Defence Minister Kim Tae-young in Seoul July 21, 2010. [Agencies]

Following the so-called "two plus two" security talks, designed to reaffirm their robust military alliance in the face of heightened tension on the Korean peninsula, US Secretary of State Hillary Clinton spoke to reporters in a joint press conference that the US will introduce new "country-specific" sanctions against the DPRK's procurement of nuclear materials.

"Today, I'm announcing a series of measures to increase our ability to prevent North Korea's proliferation, to halt their illicit activities that helped fund their weapons programs and to discourage further provocative actions," Clinton said.

"We will implement new country-specific sanctions aimed at North Korea's sale and procurement of arms and related material and the procurement of luxury goods and other illicit activities," she added.

She said UN Security Council Resolutions 1718 and 1874 will be more strictly imposed on Pyongyang, and entities and individuals engaged in illicit activities will be subject to asset freeze under the state and treasury designation.

"These measures are not directed at the people of North Korea, who have suffered too long due to the misguided priorities of their government," Clinton said, adding Washington has made it clear that there is a "path open to the DPRK" to achieve security and respect.

"North Korea can cease its provocative behavior, halt its threats and belligerence towards its neighbors, take irreversible steps to fulfill its denuclearization commitments and comply with international law," she said.

While calling on the DPRK to abandon all its nuclear programs and its pursuit of nuclear weapons, the top U.S. diplomat said stalled six-party nuclear talks, aimed at ridding Pyongyang of its nuclear programs, "is not something we are looking at yet."

Pyongyang quit the talks in April 2009.

The security talks, the first of its kind held between Seoul and Washington, were also joined by U.S. Defense Secretary Robert Gates, South Korean Foreign Minister Yu Myung-hwan and Defense Minister Kim Tae-young.

Gates, who arrived on Monday for advance talks, finalized details of joint military drills with the defense minister Kim Tae- young during a meeting a day ago.

The first joint exercise involving the US aircraft carrier USS George Washington will come on July 25 in waters off the east coast of the Korean peninsula, and is meant to deliver a "clear message" to the DPRK that provocations must be stopped, the ministers have said.

However, Rodong Sinmun, a leading newspaper of DPRK said on Wednesday that the joint military exercise to be held by South Korea and the United States "thoroughly violates the statement of the United Nations Security Council."

The UN Security Council on July 9 issued a statement over " Cheonan" warship case, unanimously deploring the attack on the South Korean warship that killed 46 sailors in March. The Council, however, stopped short of blaming the DPRK. Pyongyang has denied any involvement in the incident.

Meanwhile, China on Wednesday expressed concern over military exercises to be held by the Republic of Korea (ROK) and the United States in the Japan Sea.