North Korea says the US must apologise for calling it an "outpost of tyranny" before it will consider a return to talks on its nuclear ambitions.
North Korea says it has nuclear weapons
Pyongyang's foreign ministry said it would resume talks "any time" if the US took a "trustworthy sincere attitude", the official KCNA news agency reported.
It called on the US to "renounce its hostile policy aimed at regime change".
North Korea abruptly withdrew from the six-nation talks last month, claiming it possessed nuclear weapons.
Since late 2002, three rounds of negotiations involving the US, Russia, the two Koreas, Japan and China have sought to ease nuclear tensions on the Korean peninsula, with little success.
While the US has demanded North Korea dismantles its nuclear weapons as part of any peace deal, Pyongyang has said it needs its arsenal to defend itself against a possible US attack.
'Axis of evil'
A memorandum from the North Korean foreign ministry, quoted by KCNA, singled out remarks made by US Secretary of State Condoleezza Rice at her Senate confirmation hearing in January.
Ms Rice identified North Korea as one of six "outposts of tyranny" where the US must help bring freedom.
The comments were reminiscent of President George W Bush's "axis of evil" speech in 2002, in which he identified Iraq, Iran and North Korea as threats to US security.
The foreign ministry objected to both descriptions, saying: "The US should apologise for his above-said remarks and withdraw them, renounce its hostile policy aimed at a regime change in the DPRK [North Korea] and clarify its political willingness to co-exist with the DPRK in peace and show it in practice."
Last week, the agency quoted leader Kim Jong-il as saying North Korea would negotiate any time "if there are mature conditions".
However, he did not spell out what these conditions might be.