NATO's secretary-general Jens Stoltenberg on Thursday said he condemned North Korea's failed satellite launch, adding he called upon the country to "cease these provocative actions."

A North Korean satellite launch on Wednesday ended in failure, sending the booster and payload plunging into the sea, North Korean state media said.

North Korea's Kim Yo Jong, leader Kim Jong Un's sister, said her country would soon put a military spy satellite into orbit and promised Pyongyang would increase its military surveillance capabilities, state media KCNA reported earlier on Thursday.