MINUTEAE on the planned talks between US President Donald Trump and North Korean leader Kim Jong-un remains unclear with no agreement yet on the location or agenda, BBC has reported.
South Korea says it has not received a response from Pyongyang on a summit between North Korean leader and US President.
In a shocking development, Trump last Friday accepted North Korea's invitation to direct talks.
South Korean officials said Kim was prepared to give up his nuclear weapons.
Analysts are skeptical about what can be achieved through talks given the complexity of the issues involved.
"We have not seen nor received an official response from the North Korean regime regarding the North Korea-US summit," a spokesman for the South Korean Ministry of Unification said today.
"I feel they're approaching this matter with caution and they need time to organize their stance."
South Korean officials who spoke to Trump are now on the way to China and Japan to brief the leaders of each country on the upcoming talks.
South Korean President Moon Jae-in's top security adviser, Chung Eui-Yong, is scheduled to meet up Chinese President Xi.
In the meantime, Suh Hoon, chief of the intelligence agency, is headed to Tokyo to speak with Prime Minister Shinzo Abe.
The surprise proposal for the summit comes after more than a year of heated rhetoric between North Korea and the US and global concern that the hostilities might escalate into military confrontation.
North Korea has conducted several nuclear experiments over the past year and developed long-distance missiles it says can carry nuclear bombs as far as the US mainland.
Talks between the countries would mark an unprecedented step in the conflict as no sitting US president has ever met with a North Korean leader.