Amid rising tensions over Iran’s nuclear program, the United States has reached out to a number of “like-minded countries,” including Japan, regarding options to ensure freedom of navigation in the Persian Gulf, the visiting Saudi Arabian state minister for foreign affairs said Tuesday in Tokyo.

Adel al-Jubeir, who came to Japan for the Group of 20 Osaka summit, declined to comment on which specific options are now being discussed between the countries, which he also declined to name.

But he said the options now being studied included both military and economic measures as well.

“I think Japan has huge interests in the Middle East. … Any threat to freedom of navigation in the Gulf would have impact on not only Japan but also the global economy,” he said.

“Discussions are ongoing so I don’t want to get into details. But the key is that every country should contribute one way or another,” he said.

“It’s not an alliance. The whole world has a stake in keeping the principle of freedom of navigation,” he added.

The minister reiterated that while “specialists” in those countries are now reviewing possible options, he himself was not in a position to comment in any more detail.

If Japan is asked to make a military contribution by sending Self-Defense Forces to the Persian Gulf, it would be likely to spark a heated political debate among the public given Japan’s pacifist, war-renouncing Constitution.

On June 24, U.S. President Trump argued over Twitter that Japan and China should protect their own oil tankers traversing the Strait of Hormuz, through which about 80 percent of Japan’s oil imports are transported.

“So why are we protecting the shipping lanes for other countries (many years) for zero compensation. All of these countries should be protecting their own ships on what has always been…. a dangerous journey,” Trump tweeted.

The U.S. president’s remarks came after a Japanese tanker was attacked in the Gulf of Oman on June 13 while Prime Minister Shinzo Abe was making a historic visit to Iran.

During the interview, al-Jubeir also commented on the murder of Saudi Arabian journalist Jamal Khashoggi, which he said was a “painful episode.” But he added that a United Nations report on the crime was “ridiculous.” The report, written by U.N. investigator Agnes Callamard, claimed Saudi Arabia’s Crown Prince Mohammed bin Salman bears responsibility for the killing.

While the trials of suspects continue in Saudi Arabia, none of the country’s leadership, including the crown prince, was involved in the murder, the minister claimed.

The gruesome murder has badly damaged public perceptions of Saudi Arabia internationally. But the minister denied that it had discouraged foreign investors from putting money into the country or that it has negatively affected Saudi Vision 2030, which calls for industrial reforms to reduce the country’s dependency on oil production.

“We have seen capital outflows from emerging markets over the last six month, and we have seen inflow of more than $12 billion into Saudi Arabia,” the minister said.