The U.S. and South Korea want to bring North Korea back into talks to denuclearise.
On Monday Washington's special envoy for North Korea Sung Kim met with his counterpart in Seoul.
His visit comes amid a simmering new standoff over Washington and Seoul's annual joint military exercises that Pyongyang warned could trigger a security crisis.
The North sees these exercises as a rehearsal for war against it.
But Kim tried to tamp down that tension.
"The United States does not have hostile intent towards the DPRK (Democratic People's Republic of Korea). The ongoing U.S.-ROK (Republic of Korea) combined military exercises are longstanding, routine, and purely defensive in nature, and support the security of both of our countries.
He also urged Pyongyang to come to the table.
"I continue to stand ready to meet with my North Korean counterparts anywhere, at anytime. On the importance of the U.S.-ROK alliance, I cannot put it better than President Biden himself. He called the U.S. commitment to the defence of the Republic of Korea sacred."
A brief thaw in relations between the two Koreas in June saw a hotline between the two reopen last month.
That was a year after North Korea suspended them.
But the moment didn't last.
After preliminary training for the exercises began last week the North stopped answering the phone.
State media in Pyongyang has so far also been silent since the start of the drills.
That's despite fears that the country could conduct a missile test or take other actions to display its disapproval.