U.S. President Barack Obama is not going to attend the 70th anniversary celebration of the Soviet Union's World War II victory in Moscow on May 9. Washington apparently does not want President Park Geun-hye to go either.

Deputy U.S. National Security Adviser Ben Rhodes told reporters Monday that Obama "does not plan to travel to Moscow."

Asked what the White House's response would be if Park attends the event, Rhodes said that although it is up to individual leaders to decide, it is important to deliver a "unified voice" against Russia, which is stoking a civil war in Ukraine.

He added that Russia's outdated attempts to "redraw the map" of the Ukraine cannot be condoned and urged all countries to rally behind international principles.

The comments have deepened worries at Cheong Wa Dae. The presidential office has reportedly been divided over whether Park should go as North Korean leader Kim Jong-un has accepted the invitation.

Foreign Minister Yun Byung-se told lawmakers Tuesday that Seoul needs to "take a wait-and-see approach," since the North has yet officially to announce Kim's travel plans and only a few countries have said they will attend.