South Korean President Yoon Suk Yeol (left) shakes hands with US President Joe Biden at the White House in Washington on Tuesday. (Yonhap)

WASHINGTON -- Leaders of South Korea and the United States adopted a declaration to strengthen extended deterrence against provocations from North Korea at their summit on Wednesday, in an agreement that formalized consultations with Seoul on the decision making process.

Under the Washington Declaration, South Korea and the US will launch a nuclear consultation group as a new mechanism to focus on nuclear and strategic planning issues. It would facilitate "systematic operations" of information sharing and the movements of strategic assets of the two countries.

The new plan will provide South Korea with additional insight into how the US approaches planning for major contingencies, according to officials at the South Korean presidential office and the White House.

“We'll announce that we intend to take steps to make our deterrence more visible through the regular deployment of strategic assets, including a US nuclear ballistic submarine visit to South Korea, which has not happened since the early 1980s,” a White House official said prior to the summit.

The plan also includes strengthening joint training, simulating activities and integrating South Korea's conventional assets into the US' strategic planning. The declaration will also reaffirm South Korea's commitment to its obligations under the Non-Proliferation Treaty, he said.

“I'll be crystal clear, there is no vision of returning the US tactical or any other kind of nuclear weapon to the Korean Peninsula as there was in the Cold War,” the official said. “We believe that those efforts should be preserved even in the face of challenges from North Korea and elsewhere.”

The Washington Declaration will differ from NATO nuclear sharing, since the US does not deploy tactical nuclear weapons to the Korean Peninsula, unlike in Europe. NATO's nuclear sharing is a concept in NATO's policy of nuclear deterrence that allows member countries without nuclear weapons of their own to participate in the planning for the use of nuclear weapons by NATO.

The summit was held on the third day of President Yoon Suk Yeol's state visit to the US, the first by a South Korean leader in 12 years.

At the summit, the two discussed areas of cooperation ranging from cybersecurity and economic investments to educational partnerships, to highlight the 70th anniversary of their alliance.

On the economic front, the two sides were to coordinate their chip investments amid reports that Washington has pushed Seoul to take its side in its rivalry against China.

The summit also took place amid recent allegations that the US spied on top Korean officials, which instigated the opposition to attack the Yoon administration in Seoul. Yoon, however, said the alliance will not be shaken by the alleged eavesdropping, according to an interview with NBC News.