North Korean media has published fresh pictures of leader Kim Jong Un riding a white horse on a sacred mountain, imagery that experts say is heavy with symbolism and may indicate a policy announcement.

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

Mr Kim was pictured leading a squad of riders in a white forest near Mount Paektu.

He was wearing a black leather trenchcoat he has worn recently to open a flagship construction project and supervise a weapons test.

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 the country'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 agency also released new images of Mr Kim in a light brown coat with fur collar at the summit of the mountain, to which he previously rode in October. 

Analysts say that pictures of Mr Kim at Mount Paektu, a physically dramatic location that is ubiquitous in North Korean imagery, represent assertions of leadership and legitimacy, given the historical background.

According to North Korean propaganda, his father was born at a secret camp in the area, where his own father, the North's founder Kim Il Sung, was fighting Korea's Japanese colonial occupiers. 

According to independent historians and Soviet records, however, Kim Jong Il was born in Russia, where his father was in exile.

Mr Kim tends to visit once or twice a year, trips that are sometimes seen as indicators of policy changes.

He went to the area in November 2013, ahead of his purge and execution of his once-powerful uncle Jang Song-thaek.

And he climbed the mountain in December 2017 shortly before the diplomatic rapprochement that led to his Singapore summit with US President Donald Trump - the first between leaders of the North and the US.