SEOUL — South Korea warned on Tuesday it could consider supplying weapons to Ukraine in response to North Korea allegedly dispatching troops to Russia, as both Pyongyang and Moscow denied the movements, which the North Atlantic Treaty Organization's (NATO) chief said would mark a 'significant escalation.'

The warning was apparently meant to discourage Russia from bringing in North Korean troops for its war in Ukraine. South Korean officials worry that Moscow may reward Pyongyang by giving it sophisticated weapons technologies that can boost the North's nuclear and missile programs that target the South.