North and South Korea, the US, and China agree in principle to declare a formal end to the Korean War which ended in an armistice, says the South's President Moon Jae-in,
BBC reports.
But talks have yet to begin because of North Korea's demands, he added.
The Korean War, which lasted from 1950 to 1953, split the peninsula into two.
North and South Korea have technically been at war ever since - backed by China and the US respectively - and locked in a tense relationship.
Having made engagement with the North a cornerstone of his presidency, Mr. Moon has long advocated for a formal declaration to the end of the conflict. But observers believe that it would be very difficult to achieve.
Mr. Moon, who is currently visiting Australia, was speaking at a joint press conference in Canberra along with Australian Prime Minister Scott Morrison.
In September Kim Yo-jong, the powerful sister of North Korean leader Kim Jong-un, signaled that her country could be open to talks, but only if the US dropped what she called a "hostile policy" against them.
North Korea consistently objects to the presence of US troops in South Korea; the joint military drills held every year between the US and South Korea; as well as US-led sanctions against North Korea's weapons programme.
But the US has repeatedly said that North Korea must first abandon its nuclear weapons before any sanctions can be lifted.
On Monday, Mr. Moon said that North Korea was continuing to make this demand as a pre-condition to discussions.
The South Korean leader has previously argued that a formal declaration to end the war would encourage the North to give up its nuclear weapons.
