Kim Kye-gwan, the Foreign Ministry Adviser, also stressed that the North would never engage in a negotiation to exchange its core nuclear facility for partial sanctions relief as it did in the no-deal Hanoi summit between US President Donald Trump and North Korean leader Kim Jong-un in February 2019, reports Yonhap News Agency.
"It can be said that the reopening of dialogue between North Korea and the US may be possible only under the condition of the latter's absolute agreement on the issues raised by the former, but we know well that the US is neither ready nor able to do so," the North's state-run KCNA news quoted the Adviser as saying.
"We know well about the way we should go and will go on our way," he added.
Kim Kye-gwan added that "there will never be such negotiations as that in Vietnam, in which we proposed exchanging a core nuclear facility of the country for the lift of some UN sanctions in a bid to lessen the sufferings of the peaceable people even a bit".
Calling the relations between the leaders of the US and the North "not bad", the former negotiator said that the North received Trump's personal letter congratulating the North Korean chairman on his recent birthday.
But he said it would be "absent-minded" to anticipate the North's return to dialogue because of the leaders' friendly relations.
The US and the North last held their working-level nuclear talks in Sweden in October 2019, reports Yonhap News Agency.
But the negotiation ended fruitlessly with Pyongyang accusing Washington of having come to the table empty-handed.
Since then, the North has ramped up pressure on the US to show flexibility to break the logjam in the negotiations with provocative saber-rattling and rhetoric.
The US has continued to signal that the door for dialogue remains open.
( With inputs from IANS )