But this week's inter-Korean summit saw the North's Kim Jong-un agreeing to shut a major missile launch site.
South Korean President Moon Jae-in also gave an unprecedented speech in front of tens of thousands of North Koreans.
Mr Kim "agreed on a way to achieve denuclearisation" on the Korean peninsula following the summit with his South Korean counterpart, Moon Jae-in.
Mr Pompeo said it was "on the basis of these important commitments" that the US was "prepared to engage immediately in negotiations".
In a statement, he said he had invited North Korean Foreign Minister Ri Yong-ho to meet him in New York next week, while invitations had been extended for a second meeting between North Korean and US representatives in Vienna, Austria.
"This will mark the beginning of negotiations to transform US-DPRK [North Korea] relations through the process of rapid denuclearisation of North Korea, to be completed by January 2021, as committed by Chairman Kim, and to construct a lasting and stable peace regime on the Korean Peninsula," he said.
The January 2021 date is the most specific timeline an official on either side has put forward publicly so far. (BBC)