Officials from major political parties on Sunday debated whether Self-Defense Forces troops should take part in a U.S.-proposed coalition to safeguard strategic waters near the Strait of Hormuz amid reports the government is mulling such a move.

Koichi Hagiuda, executive acting secretary-general of the ruling Liberal Democratic Party, stressed the need to consider a response to the proposal but said the current situation does not require the immediate dispatch of SDF troops to the Middle East.

“We can’t behave as if we are not an interested party,” Hagiuda said during a TV appearance. “Cooperation with the international community is important. Some 80 percent of vessels transporting (oil) to Japan pass through the strait.”

Tetsuo Saito, secretary-general of Komeito, the junior coalition partner of the LDP, said Japan should consider how it can make contributions by looking at the law on the fight against piracy, under which Maritime SDF vessels and patrol aircraft have been sent to waters off Somalia.

By contrast, Tetsuro Fukuyama, secretary-general of the main opposition Constitutional Democratic Party of Japan, called any dispatch “absolutely impossible under current law.”

Akira Koike, head of the secretariat of the Japanese Communist Party, and Hajime Yoshikawa, secretary-general of the Social Democratic Party, also said they were opposed the dispatch of SDF troops.

The debate comes as sources said the government is carefully examining the possibility of dispatching the SDF in response to the U.S. plans.

The administration of Prime Minister Shinzo Abe is expected to take action on the matter after the July 21 Upper House election, the sources said.

The government is facing a tough decision as its move could provoke a strong public backlash, according to the sources.

“Japan will continue diplomatic efforts to ease tensions in the Middle East and stabilize the regional situation through cooperation with the United States and other countries concerned,” Chief Cabinet Secretary Yoshihide Suga said at a news conference on Friday.

Suga stopped short of denying that Tokyo has been approached by Washington on the proposed military coalition. Japan has been engaging in various exchanges with the United States, he said, while declining to give details.

Under one feasible option, the government could dispatch the SDF for maritime security operations, a move which would fall within the law, the sources said.

The SDF is allowed to protect Japanese ships as well as vessels carrying goods bound for Japan and can conduct on-the-spot inspections of suspicious ships. But the scope of such operations is very limited and weapons can only be used for self-defense.

Still, the sources said, the SDF personnel may not be able to serve in the military coalition as envisaged by the United States.

Since 2009, Japan has been sending MSDF destroyers and P-3C patrol aircraft to the Gulf of Aden off Somalia, which the anti-piracy law permits.

Under the law, the SDF can protect non-Japanese ships, but it only allows for action to be taken against pirates, not threats from ships controlled by foreign governments.

The national security laws, which came into force in 2016, can also be used to provide a rationale for the sending of SDF troops to the Strait of Hormuz.

If the government believes the situation in the strategic waterway could put the nation’s security at risk, the SDF can provide logistical support to the U.S. military and an international military coalition.

The SDF can also offer such support if Japan takes part in an international coalition to safeguard peace and security under a U.N. resolution.

But it would not be easy for the government to send SDF troops to the strait under either scenario because Diet approval is needed, sources said.

Under the current laws or a U.N. resolution, Japan would also be unable to carry out policing activities, the sources said.

Some people claim that Japan is theoretically allowed to send SDF troops by exercising the right to collective self-defense, which was enabled under the security legislation. But a prerequisite for exercising the right can be met only after armed conflict occurs between states.

Another option is to create special one-off legislation, but it would take time to enact such a law, the sources said.

Japan will not be able to dispatch SDF troops to the proposed coalition under its existing legal system, a veteran LDP lawmaker said. “A special law is the only option,” the lawmaker added.

As the Abe administration has claimed that the national security laws allow Japan to seamlessly respond to any situation, however, the government may face public criticism if it moves to craft special legislation, the sources said.