North Korea's media outlets on Sunday redoubled calls for "self-reliance" as its nuclear negotiations with the United States remain in limbo, with little progress in its efforts to ease international sanctions.

In recent weeks, Pyongyang has been hammering away at the self-reliance campaign, apparently to strengthen national unity amid Washington's hard-line stance in the nuclear negotiations and a lack of substantive headway in key inter-Korean cooperation projects.

In an editorial, the Rodong Sinmun, the daily of the North's ruling Workers' Party, called on North Koreans to follow the party leadership to construct a "self-sustaining economy" at a time of continued sanctions pressure.

"Thoroughly establishing the party leadership system is a significant demand to hold up highly the banner of independence and self-reliance and press ahead with the construction of socialist economy," the newspaper said.

"Especially, the trend of today's political situation -- where hostile forces' instigation of sanctions has become more explicit calls for raising the banner of independence and self-reliance," it added.

The communist state has been seeking to secure sanctions relief from the U.S. in return for its phased, incremental denuclearization steps. But Washington has demanded Pyongyang take sweeping disarmament steps before any rewards are given.

Such gaps led to the breakdown of the second summit between U.S. President Donald Trump and North Korean leader Kim Jong-un in Hanoi in February. Since the summit, the bilateral negotiations have been stalled. 

Uriminzokkiri, a North Korean propaganda website, also called for self-reliance, saying it is the only way to chart a "path to a brighter future."

"The banner of self-reliance is the driving force that has allowed our people to achieve the best outcome in a short period time in the midst of worst hardships," it said. 

The website also took a swipe at the plan by South Korea and the United States to stage a summertime combined exercise.

"(The exercise) is a vicious challenge to our nation and the international community and the violent violation of inter-Korean declarations ... This is a flame that could escalate tensions on the Korean Peninsula and drive the North-South relations into a catastrophe," it said. (Yonhap)