HANOI, Feb 28 - North Korean leader Kim Jong Un said on Thursday he was willing to give up his nuclear weapons and he would not be holding a second summit with U.S. President Donald Trump in Vietnam if he were not.

Kim and Trump began a second day of talks earlier on Thursday in the Vietnamese capital, Hanoi, with both expressing hope for progress on improving relations and the key issue of denuclearisation.

“If I’m not willing to do that, I won’t be here right now,” Kim told reporters through an interpreter, when asked if he was ready to give up his nuclear weapons.

Trump, responding to that, said: "That might be the best answer you’ve ever heard.”

The two leaders were sitting across from each other at a conference table, with their aides.

North Korea's leader Kim Jong Un and U.S. President Donald Trump attend the extended bilateral meeting in the Metropole hotel with their aides, during the second North Korea-U.S. summit in Hanoi, Vietnam February 28, 2019. Photo: Reuters

Kim did not elaborate on what "denuclearisation" would entail, but asked if he was ready to take concrete steps, Kim said they had just been talking about that.

"Hope you give us more time to talk. Even a minute is precious," he told reporters.

While the United States is demanding North Korea give up all of its nuclear and missile programmes, the North wants to see the removal of a U.S. nuclear umbrella for its Asian allies such as South Korea and Japan.

After this first session of the second day of summit talks, lasting about half an hour, Trump and Kim took a brief stroll in the courtyard of the Hanoi hotel where they were meeting.

They were joined by Kim's top envoy Kim Yong Chol, U.S. Secretary of State Mike Pompeo and interpreters.

They chatted and gestured in the leafy courtyard of the French-colonial era Metropole hotel, before returning indoors.