US President Joe Biden and the leaders of Japan and South Korea agreed on Friday to expand security and economic ties at a historic summit at the US presidential retreat of Camp David.

Their meeting and agreement come at a time that the three countries are at an increasingly tense point in their relations with China and North Korea.

Mr Biden said the three countries would establish a hotline to discuss responses to threats and announced the agreements, including what they have termed the “Camp David Principles”, at the close of his talks with South Korean President Yoon Suk Yeol and Japanese prime minister Fumio Kishida.

“The purpose of our trilateral security co-operation is and will remain to promote and enhance peace and stability throughout the region,” they said in a joint statement.

The three leaders agreed to “improve our trilateral communication mechanism to facilitate regular and timely communication between our countries, including our national leadership,” the statement said.

“That will include yearly trilateral meetings between leaders, foreign ministers, defence ministers and national security advisers.”

Opening the meeting, Mr Biden said: “Our countries are stronger and the world will be safer as we stand together. And I know this is a belief that all three share.”

Mr Yoon said as the men appeared before reporters that “today will be remembered as a historic day, where we established a firm institutional basis and commitments to the trilateral partnership”.

And Mr Kishida said before the private talks that “the fact that we, the three leaders, have got together in this way, I believe means that we are indeed making a new history as of today. The international community is at a turning point in history”.

The US, Japan and South Korea agreed to a new “duty to consult” security pledge, committing the three countries to speak to each other in the event of a security crisis or threat in the Pacific.

The “duty to consult” pledge is intended to acknowledge that the three countries share “fundamentally interlinked security environments” and that a threat to one of the nations is “a threat to all”, according to a senior Biden administration official.

Under the pledge, the three countries agree to consult, share information and align their messaging with each other in the face of a threat or crisis, the official said.

Mr Biden’s focus for the summit was to nudge the United States’ two closest Asian allies to further tighten security and economic co-operation with each other.

Beijing sees the tightening co-operation efforts as the first steps of a Pacific-version of Nato, the transatlantic military alliance, forming against it.

US officials expect that North Korea will lash out, perhaps with more ballistic missile tests and certainly blistering rhetoric.