North Korea said Wednesday that it won't allow outside inspectors to take samples from its main nuclear complex to verify the communist regime's accounting of past nuclear activities. Pyongyang's Foreign Ministry said in a statement that it never agreed to such sampling, contradicting statements by US officials last month following a breakthrough deal about how to verify North Korea's list of nuclear programs the regime submitted in June under a disarmament pact. The conflicting statements could prove a new snag in the long, tortured process of nuclear disarmament on the Korean peninsula. North Korea has agreed to give up its nuclear weapons but has bickered with the US over verification, with Washington insisting on strict measures to ensure Pyongyang is not hiding any active atomic programs. US officials said last month that North Korea had agreed to allow atomic experts to take samples and conduct forensic tests at all of its declared nuclear facilities and undeclared sites on mutual consent. Sample-taking is believed to be a key means of nuclear verification. On Wednesday, the North's Foreign Ministry said last month's deal with Washington calls only for letting nuclear inspectors visit its main atomic complex, view related documents and interview scientists - but it said taking samples was never part of the deal. Pyongyang also said only its Yongbyon atomic complex is subject to verification, and inspections can take place only after it receives all energy aid promised from its negotiating partners - China, Japan, South Korea, the United States and Russia. "It is an act of infringing upon sovereignty little short of seeking a house-search ... to insist on adding even a word except the written agreement reached between" the two countries, said the statement carried by the North's official Korean Central News Agency. The US Embassy in Seoul had no immediate comment on the North's statement. If the North's statement is true, it provides the first details about last month's negotiations in Pyongyang between the North and the chief US nuclear envoy Assistant Secretary of State Christopher Hill. That deal led to Washington removing Pyongyang from its terrorism blacklist and North Korea resuming disabling its nuclear facilities that the regime had suspended for two months amid the verification row. In February 2007, North Korea agreed to disable Yongbyon and declare all its nuclear programs as a step toward their ultimate dismantlement. In exchange, the impoverished communist nation was promised energy aid worth 1 million tons of fuel oil and other concessions, including removal from the US terrorism list. In Wednesday's statement, the North also complained about a delay in energy aid shipment, saying it has slowed disabling the Yongbyon nuclear reactor in response. About half of the promised aid has been provided so far, while the North has completed eight of 11 required steps to disable the nuclear complex. Pyongyang has claimed the pace of energy shipment does not match that of its disabling work. Last month's US-North Korea deal on verification has been awaiting endorsement at formal six-nation nuclear talks that have yet to be scheduled. North Korea said Wednesday that it had agreed to a proposal from host China that the talks convene on Oct. 18, claiming that it was not its fault that the negotiations have not taken place yet. Pyongyang alarmed the world in 2006 by setting off a test nuclear blast. It then agreed to dismantle its nuclear program in exchange for energy aid and political concessions.