SEOUL, South Korea — Ramping up pressure on the United States, North Korea on Tuesday accused the Trump administration of demanding too much but offering too few concessions in its negotiations over the terms of denuclearizing the North.

Up to now, North Korea has demanded almost daily that the United States join North and South Korea in declaring an end to the Korean War as an initial confidence-building concession from Washington before taking steps to denuclearize. The war was halted with a truce in 1953 but a peace treaty was never signed.

The United States insists that before it grants any concessions to North Korea, the North must do more to keep its end of the deal Kim Jong-un reached in his talks with President Trump in Singapore in June — when the North Korean leader promised to “work toward the complete denuclearization of the Korean Peninsula.”

United States officials and analysts have called on the North to submit a full inventory of its nuclear program for verification and to start dismantling its nuclear and missile facilities.