Choe Son Hui, North Korea's foreign ministry director general for US affairs, made the comment to reporters in Beijing as she was travelling home from Norway, Yonhap said.
"We'll have dialogue if the conditions are there," she told reporters when asked if the North was preparing to hold talks with the Trump administration, according to Yonhap.
When asked if North Korea was also preparing to talk with the new government in South Korea, of liberal President Moon Jae-in, Choe said: "We'll see."
The comments by Choe, who is a veteran member of the North's team of nuclear negotiators, came amid stepped up international efforts to press North Korea and ease tension over its pursuit of nuclear arms.
US President Donald Trump warned in an interview with Reuters in late April that a "major, major conflict" with the North was possible, but he would prefer a diplomatic outcome to the dispute over its nuclear and missile programmes.
Trump later said he would be "honoured" to meet the North's leader, Kim Jong Un, under the right conditions.
A source with knowledge of the latest meeting said at least one former US government official took part but the US administration was not involved.
South Korea's Moon, elected this week on a platform of a moderate approach to North Korea, has said he would be willing to go to Pyongyang under the right circumstances and said dialogue must be used in parallel with sanctions to resolve the problem over North Korea's weapons.
North Korea has conducted five nuclear tests in defiance of UN and US sanctions and is also developing long-range missiles to deliver atomic weapons.
It says it needs such weapons to defend itself against US aggression.
(Reporting by Jack Kim; Editing by Robert Birsel)