North Korea accused its nuclear negotiating partners Friday of being too slow in shipping fuel oil under an aid-for-disarmament deal.

The North’s Foreign Ministry said in a statement that it has completed 80 percent of the work required to disable its main nuclear complex, but countries involved in six-nation disarmament talks have only sent 40 percent of promised energy shipments to the North.

The ministry statement said the North will only move on to the next phase of the denuclearization process after it is awarded promised energy aid and political benefits.

Energy-starved North Korea was promised aid equivalent to 1 million tons of heavy fuel oil under the deal with South Korea, the U.S., China, Japan and Russia.

The statement said the North has shown its resolve to disarm by destroying a cooling tower at its Yongbyon nuclear complex.

North Korea submitted a long-awaited atomic declaration last week, raising hopes for a breakthrough in stalled talks on its nuclear programs. In exchange, Washington lifted some economic sanctions against the North and began steps removing the country from a U.S. State Department list of state sponsors of terrorism.

The North’s statement, however, said the U.S. move to take it off the terrorism list has not become effective.