No sanctions relief for N Korea until denuclearisation: Mattis

United States Defense Secretary James Mattis on Sunday, taking a hard line on North Korea, said the reclusive country will get relief from international sanctions only when it has demonstrated "verifiable and irreversible" steps to denuclearisation.

"We can anticipate, at best, a bumpy road to the negotiation. We must maintain a strong collaborative defensive stance so we enable our diplomats to negotiate from a strong position of strength in this critical time," CNN quoted Mattis, as saying.

"We must remain vigilant, and we will continue to implement all UN security council resolutions on North Korea. North Korea will receive relief only when it demonstrates verifiable and irreversible steps to denuclearisation," he added.

Mattis' remarks came while he was speaking alongside South Korean and Japanese defense ministers at the Shangri-La Dialogue, the report said.

The remarks of US Defense Secretary come barely days prior to the much-anticipated US-North Korea summit.

On Friday, United States President Donald Trump confirmed that the US-North Korea summit will take place on June 12 in Singapore as scheduled earlier.