The U.S. government has reaffirmed a neutral stance over a diplomatic conflict between China and Japan over the disputed Senkaku Islands in the East China Sea.

U.S. State Department spokeswoman Victoria Nuland said in a news briefing on Monday that Washington wants China and Japan to work out the issue peacefully. She then added that the U.S. doesn’t “take a position on the sovereignty there.”

Nuland did say, however, that if reports about an attack on the vehicle of the Japanese ambassador in Beijing are accurate, “that would be extremely concerning, particularly given his diplomatic status.”

Japan has effective control of the Senkaku Islands, as they're known in Japanese, but China also claims the islands, called Diaoyu in Chinese.