Nagasaki's mayor said last week that Israel's ambassador Gilad Cohen was not invited to Friday's event in the southern Japanese city because of the risk of possible protests over the Gaza war.

The US and British embassies said on Wednesday that their ambassadors would not take part as a result and that their countries would be represented by lower-ranking diplomats.

Media reports said that Australia, Italy, Canada, and the European Union, who together with the United States, Britain, and Germany signed a strongly worded joint letter to Nagasaki's mayor last month, would follow suit.

US ambassador Rahm Emanuel will not attend "after the mayor of Nagasaki politicized the event by not inviting the Israeli ambassador", an embassy spokesperson told AFP.

Instead, Emanuel, who was ex-president Barack Obama's chief of staff, will go to a separate event at a temple in Tokyo, the spokesperson said.

The British embassy said that Ambassador Julia Longbottom would also not be in Nagasaki, saying that not inviting Israel "creates an unfortunate and misleading equivalency with Russia and Belarus -- the only other countries not invited to this year's ceremony".

A spokesperson for the French embassy said that its number two would attend, telling AFP that the "decision not to invite the representative of Israel is regrettable and questionable".

Nagasaki mayor Shiro Suzuki said last week that the decision not to invite Cohen was "not politically motivated" but based on a desire to "hold the ceremony in a peaceful and somber atmosphere".

In June Suzuki said Nagasaki had sent a letter to the Israeli embassy calling for an "immediate ceasefire" in Gaza.

In their letter to Suzuki seen by AFP, the six Western envoys had warned that if Israel was excluded "it would become difficult for us to have high-level participation at this event".

Government spokesman Yoshimasa Hayashi declined to comment on Wednesday, saying invitations were "a decision for the organizer, Nagasaki City."

In January, The United Nations’ top court ordered Israel to do all it can to prevent death, destruction, and any acts of genocide in Gaza.

In May, the International Criminal Court prosecutor's office requested arrest warrants for Israeli Prime Minister Benjamin Netanyahu, and his defense chief Yoav Gallant, for alleged war crimes and crimes against humanity.

Israel has killed more than 39,653 Palestinians in Gaza, mostly children and women, since it started its genocidal war on the Palestinian territory.

 About 90% of the population of  Gaza have been displaced at least once since the war began, according to the UN’s humanitarian agency.