"Our goal remains the complete denuclearization of the Korean peninsula," Biden's press secretary, Jen Psaki, told reporters.

US policy will see "a calibrated, practical approach that is open to and will explore diplomacy" with North Korea, she said.

Psaki gave little indication of what kind of diplomatic initiative this could entail, but suggested that Biden had learned from the experience of previous administrations, who have struggled for decades to deal with the dictatorship in North Korea or, in recent years, its growing nuclear arsenal.

She said Washington would not "focus on achieving a grand bargain," apparently referring to the kind of dramatic over-arching deal that Donald Trump initially suggested was possible when he met with North Korea's leader Kim Jong-un.

Neither would the White House follow the more standoff approach called "strategic patience," espoused by Barack Obama, Psaki said.

In April, South Korean President Moon Jae-in, who is due to visit the White House on May 21, urged Biden to engage directly with Kim on denuclearization.

Moon told the newspaper he favored "top-down diplomacy."