“We are aware of North Korean missile launches this morning into the East Sea,” the US Indo-Pacific Command spokesman Captain Mike Kafka said in the initial official statement from the US government.

North Korea launched two suspected ballistic missiles into the sea near Japan, drawing condemnation and concern from Japan, the US, and South Korea.

The US military’s use of the term “East Sea” made a splash of its own in Japan, which prefers the name “Sea of Japan”.

Deputy Chief Cabinet Secretary Manabu Sakai told a news conference that the use of East Sea was “inappropriate”.

“Japan’s stance on this issue is that ‘Sea of Japan’ is the one and only official, international name for this body of water,” he said.

“We have already made our position on this issue clear to the US and are currently requesting a correction.”

The command later issued a correction saying Kafka’s statement should have referred to the Sea of Japan or waters off the east coast of the Korean Peninsula.

“The US has not changed its position on using Sea of Japan as the sole approved name for the geographic feature,” the correction said.

The Japanese consternation highlights the challenges for the new Biden administration, which has vowed to rebuild relations with its allies in Asia.

South Korea, which was occupied by Japan from 1910-1945, argues the area of ocean should be known by what it sees as the neutral name “East Sea”.

The sea is also the location of islets that both South Korea and Japan claim. South Korea, which administers the outcrops, calls them Dokdo while Japan calls them Takeshima.

Those are just two areas of tension between the US allies.

Historical and economic disputes nearly led to South Korea scrapping, in 2019, an intelligence-sharing deal with Japan that had been backed and brokered by the US.

Rhetoric has since cooled but the disputes can flare up unexpectedly and complicate US efforts to coordinate Asia strategy.