In stark contrast to Prime Minister Junichiro Koizumi's unequivocal support for Washington, the four opposition parties lashed out Thursday against the U.S.-led attack on Iraq.

The Democratic Party of Japan, Liberal Party, Japanese Communist Party and Social Democratic Party said the pre-emptive strike, which came without United Nations authorization, is in violation of international law.

Expressing support for such action deviates from Japan's basic diplomatic policy of turning to the U.N. as the key authority to maintain global peace and stability, they said in their statements.