Japan's new cabinet on Monday vowed to work to extend support to US-led military operations in Afghanistan despite objections by the resurgent opposition.

Japanese ships in the Indian Ocean provide refueling and other support under special laws passed after the September 11, 2001 attacks allowing officially pacifist Tokyo to be part of the US-led "war on terror."

"The prime minister told me to work earnestly on the special anti-terrorism laws and realignment of US forces" in Japan, Defence Minister Masahiko Komura told his inaugural news conference.

"I believe working sincerely on what I was told by the prime minister will lead to a rise in support for the cabinet" among voters, he said.

Prime Minister Shinzo Abe, a staunch advocate for a greater Japanese military role, is languishing in the polls following a series of scandals that hit the previous cabinet.

The leader of the opposition, which seized control of the upper house of parliament in elections last month, has pledged to oppose renewing the laws on the Indian Ocean mission, which expire on November 1.

New Foreign Minister Nobutaka Machimura also vowed to "do my utmost" to extend the Indian Ocean mission.

"After 9/11, there was a unanimous resolution by the United Nations," Machimura said. "As a responsible member of the international community, we naturally have to do this."