North Korea’s assertion that it has tested a hydrogen bomb is straining relations with China.

But there were already signs the allies are at odds, including the abrupt cancellation of performances by Kim Jong-un’s handpicked female pop group Moranbong, who were supposed to play a series of shows in Beijing last month.

The official Chinese news agency Xinhua said at the time that “communication issues” had caused the cancellation, adding "China attaches great importance to cultural exchanges between the two countries, and is willing to work with the DPRK side to promote bilateral exchanges in culture and all other areas.”

Moranbong surprised the world in 2012 when they were first unveiled wearing high heels and miniskirts, and singing American songs like the theme from “Rocky” and Frank Sinatra’s “My Way,” all while cavorting with Disney characters like Minnie Mouse.

South Korean analysts saw the band as a signal of openness to the outside world, but North Korean papers retorted that there would be “no such policy shift as expected by western countries,” according to The Korea Foundation, a South Korean agency promoting cultural exchange.

Moranbang is made up of at least six singers and their performances feature imagery of rockets and torpedoes on giant screens behind them.

Academics writing in The Review of Korean Studies said the band instead symbolizes “the state’s drive to maintain its relevance for youth and elites in Pyongyang, who might otherwise be disposed to look (to South Korea).”

“It is surely possible to interpret the (2012) Moranbong performance as a kind of promise to the women of Pyongyang and perhaps North Korean society more broadly that a kind of material prosperity is around the corner,” the academics wrote in their 2014 analysis.

Local propaganda, they noted, said the women were also on a mission to “stimulate production in the textile sector.”

That’s apparently a common theme. North Korean singer Hyon Song-wyol -- who was rumoured to have been Kim Jong-un’s wife -- can be seen gleefully working in a textile factory in her music video “Excellent Horse Like Lady.”