A report released Monday by a nongovernmental organization said 322 financial institutions in 30 countries, including Japan, have provided credit to Boeing Co. and 19 other companies in six nations involved in the development and manufacture of nuclear weapons.

The Australia-based International Campaign to Abolish Nuclear Weapons said in the report that those financial institutions provided credit worth about $48.7 billion, or about ¥4 trillion, since 2008.

The NGO urged the financial institutions named in the report to halt such business because they are aiding the continued existence of nuclear weapons.

"By lending money to nuclear weapons companies and purchasing their shares and bonds, banks and other financial institutions are indirectly facilitating the buildup and modernization of nuclear forces," the report said.

The Japanese institutions named in the report — Mitsubishi UFJ Financial Group Inc., Mizuho Financial Group Inc. and Sumitomo Mitsui Financial Group Inc. — have provided a combined $3.53 billion, or about ¥289 billion, in credit to the so-called nuclear weapons companies, according to the NGO.

Nomura Holdings Inc. and Daiwa Securities Group Inc. have also been involved in bond sales for some of the 20 companies listed as involved in developing and manufacturing nuclear weapons.

"We can't comment on our businesses with specific companies," said an official of Mitsubishi UFJ, which the report accuses of being "among the banks and other financial institutions most heavily involved."

Two Dutch financial institutions, PGGM and Rabobank Group, have an internal policy of not providing finance to armament-related companies, the report says, adding that neither has been involved in financing any of the 20 companies since July 2008.