SEOUL - North Korean leader Kim Jong Un and his wife, Ri Sol Ju, were among the hundreds in Pyongyang on Sunday watching South Korean K-pop singers perform in the North for the first time in more than a decade as tensions between the old rivals thaw.It was the first time a North Korean leader had attended a South Korean performance in the North's capital. Kim was seen clapping in tune to some of the songs and took photographs with the performers after the show."Our dear leader comrade said his heart swelled and he was moved by the sight of his people deepen their understanding of South Korean popular culture and cheer with sincerity," the North's KCNA state media said.The North Korean audience clapped, cheered, sang along to some of the songs and later presented the South Korean performers with bouquets."(Kim Jong Un) showed much interest during the show and asked questions about the songs and lyrics," Culture Minister Do Jong-whan told reporters after the show.Sunday's performance coincided with the start of annual joint South Korean-U.S. military drills, which have previously been met with denunciations and missile launches by the North, and were delayed and shortened this year in order not to overshadow the Olympic detente.The recent thaw in relations, which could even lead to a summit between Kim and U.S. President Donald Trump in May, follows months of increased tensions after North Korea conducted missile launches and a nuclear test last year in defiance of United Nations Security Council sanctions.Sunday's concert was held under the title "Spring is Coming" at the East Pyongyang Grand Theatre, performed by an elite lineup of South Korean artists including veteran vocalists Cho Yong-pil, Lee Sun-hee, rock star Yoon Do-hyun and singer Baek Ji-young, as well as K-pop girl band Red Velvet.Like the concert title, the performance had brought a "spring of peace" to the two Koreas, Kim was also cited as saying by the North's central news agency, and expressed wishes for a "prosperous autumn."The North Korean leader's face was slightly flushed in a group photograph with the performers distributed by North Korean state media. He was seen in another directly addressing members of Red Velvet, which commands more than 4.6 million followers on Instagram.North Korean staff were spotted outside the performers' dressing rooms using Japan-made electronic devices to serve coffee and cupcakes, including Western Lavazza and Coffee-mate products, according to a South Korean media pool report.