North Korea successfully developing a nuclear-tipped intercontinental ballistic missile (ICBM) would be a “red line” for Seoul, South Korean President Moon Jae-in said on Thursday at a press conference marking his first 100 days in office.

“The red line is North Korea completing its development of ICBM and weaponizing it by mounting a nuclear warhead onto it,” Moon said.

“I think that the North has been reaching the threshold of this red line gradually. We should stop the North’s additional provocation at this stage.”

Moon warned that Pyongyang will face “more tough sanctions” if further tests were carried out – measures that,