They won over buttoned-up investors at a banking conference with their jingles about teenage love, but the K-pop girl band Red Velvet is about to face what may be its toughest audience yet: North Korea.

The chart-topping starlets will perform Sunday with 10 other South Korean music groups at the first of two concerts this week in Pyongyang. It is the latest overture in Seoul's decades-long cultural diplomacy push, aimed at softening ties with its closed off and nuclear-armed neighbor.

Taking place four weeks before a historic meeting between the two countries' leaders, the music tour could provide a test of whether North Korea's attitude to the rest of the world is truly thawing. As they belt out their dance tunes "Red Flavor" and "Bad Boy" to about 1,500 members of North Korea's elite at the East Pyongyang Grand Theater on Sunday night, Red Velvet will be hoping for a less frosty reception than those that have gone before them.