Updated

By Alastair Himmer

TOKYO (Reuters) - Nagasaki has abandoned its ambitions to host the 2020 Olympics after the Japanese Olympic Committee (JOC) rejected a joint bid with Hiroshima.

Nagasaki Mayor Tomihisa Taue informed the city's local assembly of the decision on Friday but offered full cooperation to Hiroshima should the city table a solo bid.

JOC chief Tsunekazu Takeda last month told officials of Hiroshima and Nagasaki -- the only cities to have suffered a nuclear attack -- that co-hosting was not possible.

"While the Olympic charter continues to state one city per (bid) country, the options for an atom-bombed city to stage the Games are obviously limited," Taue told Japanese reporters.

Hiroshima and Nagasaki had planned a joint bid to demonstrate their commitment to abolishing nuclear weapons.

A proposal to have Hiroshima apply and unofficially call it the "Hiroshima-Nagasaki Olympics" also fell flat.

"We remain positive (about an individual bid)," Hiroshima Mayor Tadatoshi Akiba said in a statement. "We will continue to concentrate all of our energies into realizing our dream of hosting the 2020 Olympics."

Tokyo, which lost out to Rio de Janeiro in last October's IOC vote for the 2016 Games, is also in contention to become Japan's 2020 bid city.

Tokyo Governor Shintaro Ishihara offered an olive branch to Nagasaki by suggesting some Olympic events be held in city on the southern island of Kyushu if the capital won the hosting rights.

"The idea of an 'Olympics for peace' is persuasive," Japan's Kyodo news agency quoted Ishihara as saying. "We will seek cooperation from Nagasaki City."

Tokyo staged Asia's first Olympics in 1964 while Hiroshima hosted the 1994 Asian Games. London will host the 2012 Summer Games.

(Editing by Peter Rutherford)