The Olympic teams from North and South Korea will not march together at the opening ceremony in Beijing.
International Olympic Committee president Jacques Rogge said leaders from the North and South could not agree on a joint march.
Athletes from the two countries marched under a "unification flag" in 2000 and 2004, wearing the same uniforms.
But relations have soured this year since South Korean President Lee Myung-Bak turned away from his predecessors' "sunshine policy" towards the North.
Mr Rogge said the two teams will walk one after the other at the ceremony, according to the usual way of ordering the teams alphabetically.
The frosty relations between the two countries have forced China to drop a plan to have President Lee sit next to North Korean deputy leader Kim Yong-nam at a welcome lunch on Friday.
North Korea and South Korea have been technically at war since the 1950-53 war ended without a peace treaty.
The North has sent 60 athletes to China, its closest political ally. The South has sent 260.