The talent agency for K-pop boy band BTS says the group's oldest member will join the South Korean military soon. It says the six other members are also expected to be drafted, and that all members hope to restart activities as a group in around 2025.

In South Korea, all eligible men are required to enter military service by age 28, in principle. But those who have made great contributions in their fields, such as in pop culture and the arts, are allowed to delay joining until age 30.

BTS's oldest member, Jin, faces enlistment in December when he turns 30. Some South Koreans have argued that members of the globally popular band should be granted exemption from military duties.

The agency announced on Monday that Jin will withdraw his application to postpone his enlistment by the end of October, and start serving in the military soon.

His six bandmates will focus on individual activities for the time being before joining up.

BTS held a free concert in South Korea's second largest city of Busan on Saturday that attracted tens of thousands of fans from home and other countries, including Japan.