A civic group including atomic bomb survivors has asked Hiroshima City to suspend a plan to establish sister ties between its memorial park and that of Pearl Harbor in the United States.

Representatives of Hiroshima's Peace Memorial Park and the Pearl Harbor National Memorial in the US state of Hawaii are set to sign a sister park agreement on Thursday.

The group of 10 organizations including the Hiroshima Congress against A- and H-Bombs submitted a petition on Tuesday.

It says Japan's attack on Pearl Harbor and the US bombing of Hiroshima are not things that the two sides have forgiven each other for, but historical lessons that should never be repeated.
It also says the aim of establishing sister ties between the parks is unclear.

The group argues that the decision was made abruptly without discussion involving citizens and atomic bomb survivors. It calls for suspending the signing and holding thorough discussions involving various parties.

Hiroshima officials say the US side proposed the arrangement in the run-up to the Group of Seven summit held in the city in May.

They say they will go ahead with the signing as planned, but will discuss with their American counterparts how to promote the ties, taking citizens' opinions into consideration.

Japan's attack on Pearl Harbor in late 1941 marked the beginning of the Japan-US war. The Hiroshima park memorializes the US atomic bombing of the city near the end of the war in 1945.