Democratic People's Republic of Korea (DPRK) media published new pictures of leader Kim Jong Un riding a white horse on a sacred mountain, as the DPRK announced on Wednesday it would soon convene a rare meeting of the ruling party's top leaders. 

The photos come as nuclear talks with the United States are stalled ahead of a looming end-of-year deadline set by the DPRK for some kind of concession from Washington. 

Kim, in a black leather trenchcoat he has worn recently to open a flagship construction project and supervise a weapons test, was pictured leading a squad of riders in a white forest near Mount Paektu. 

The group included his wife Ri Sol Ju as well as several officials, the images released by the official KCNA news agency showed. 

The mountain, a dormant volcano on the border with China, has great symbolic significance in the North as both the spiritual birthplace of the Korean nation and, according to Pyongyang's orthodoxy, the birthplace of Kim's father Kim Jong Il. 

The current leader toured several historic locations and climbed the mountain, KCNA said, leaving a "sacred trace in the revolutionary battle sites", through "knee-high virgin snow."

The ride was aimed at instilling in DPRK people the mountain's "indefatigable revolutionary spirit" in the face of "unprecedented blockade and pressure imposed by the imperialists," KCNA reported. 

Kim said there was a need to prepare for "the harshness and protracted character of our revolution," according to KCNA. 

The agency also released new images of Kim in a fur-lined brown coat at the summit of the mountain, to which he previously rode in October. 

He climbed the mountain in December 2017, shortly before the diplomatic rapprochement that led to his Singapore summit with Donald Trump, the first between leaders of the North and the U.S..

The announcement that a Plenary Meeting of the Central Committee of the ruling Workers' Party of Korea would meet sometime in late December underscores how the DPRK is serious about making a major decision, analysts said. 

Such meetings have often been when the DPRK has announced major policy shifts. 

Earlier this week Kim opened a huge development project in nearby Samjiyon, involving the reconstruction of an entire town. 

The ceremony and Kim's horse ride come with time running out on the North's demand for the U.S. to offer it fresh concessions by the end of the year, and ahead of Kim's New Year speech on January 1. 

Negotiations between Pyongyang and Washington have been deadlocked since the Hanoi summit broke up in February, and the North has issued a series of increasingly assertive comments in recent weeks as its time limit approaches. 

On Tuesday KCNA quoted vice foreign minister Ri Thae Song saying: "What gift the U.S. receives for Christmas depends entirely on the U.S.'s decision." 

(With input from AFP, Reuters)