A Japanese destroyer left its base in Kanagawa Prefecture for the Middle East on Sunday to join the Maritime Self-Defense Force’s first long-term intelligence-gathering mission abroad.

The 4,650-ton Takanami is scheduled to join the ongoing mission in late February. The mission commenced with the dispatch of MSDF P-3C patrol planes on Jan. 20, and is aimed at ensuring the safety of Japanese-related commercial shipping in the region, according to the government.

Prime Minister Shinzo Abe and Defense Minister Taro Kono joined the families of the around 200 ship personnel at an event to send off the vessel at the MSDF’s base in the city of Yokosuka.

“The intelligence-gathering mission bears very significant meaning that is directly linked to people’s lives,” Abe said at the event, referring to the mission’s remit to ensure the safe passage of oil tankers that carry about 90 percent of Japan’s total imports.

Japan plans to rotate MSDF destroyers in three four-month tours over the course of the one-year Middle East mission, which could be extended with Cabinet approval.

The government’s decision to deploy the MSDF assets, with a total of around 260 personnel, in the Middle East has been met with criticism by opposition parties amid rising tensions between the United States and Iran.

Japan has not joined the U.S.-led Operation Sentinel maritime security initiative near the Strait of Hormuz, a key waterway for the transportation of oil, for fear of harming Tokyo’s long-standing friendly ties with Tehran.

The MSDF will instead operate in the Gulf of Oman in the northern part of the Arabian Sea and the Bab el-Mandeb Strait connecting the Red Sea with the Gulf of Aden.

Japan has said it will only use military power to protect Japanese commercial shipping during the patrol operations.

The mission, which Japan has made sure will be operating independently from the U.S. and staying away from potential flash points in the Persian Gulf, highlights just how few American allies have signed up for Washington’s effort in the region.

U.S. allies such as Japan are walking a fine line to show support for President Donald Trump while minimizing the risk of getting drawn into a larger conflict with Iran. Many disagreed with Trump’s decision to withdraw from a 2018 Joint Comprehensive Plan of Action to curb Tehran’s nuclear program and were alarmed over a flurry of violence last month that included the U.S.’s targeted killing of top Iranian Gen. Qassem Soleimani.

While Australia and the U.K. have each committed ships and are part of the U.S.-led International Maritime Security Construct, others such as Japan, India and South Korea have sent vessels to the region with orders to act independently. France said it would deploy its Charles de Gaulle aircraft carrier to the Middle East from January to April to support European countries.

“The international response has varied from lukewarm to hostile,” said Ashley Townshend, director of foreign policy and defense at the University of Sydney’s United States Studies Center. “Most U.S. allies and partners have sensibly sought to stay out of the Persian Gulf deployment, which is — or at least could have been — an entirely avoidable mission, had Trump not withdrawn from the JCPOA and eschewed a cool-headed path of diplomacy.”

The U.S. began recruiting backers for the security coalition last summer after a series of attacks on tankers near the Persian Gulf, a strategic choke point that handles about one-third of the world’s seaborne crude oil. Trump singled out Japan among the countries that were providing “zero compensation” for U.S. protection.

Three regional rivals of Iran — Bahrain, Saudi Arabia and the United Arab Emirates — as well as Albania, have also signed up for the International Maritime Security Construct. Australia dispatched its frigate HMAS Toowoomba, while the U.K. sent the HMS Montrose and HMS Defender — a frigate and a destroyer — to accompany British-flagged ships through the Strait of Hormuz.

The demand posed a particularly difficult problem for Japan and South Korea, which used to get significant shipments of oil from Iran before the U.S. imposed sanctions. Both also rely on a large U.S. troop presence for their security and are under pressure from Trump to pay more for those deployments.

Next year, Japan is set to renew a five-year deal with the U.S. that determines how much it contributes for local staff, utilities and training relocation. Tokyo is expected to pay ¥197 billion ($1.8 billion) this year, although the U.S. doesn’t publish the costs of maintaining the bases.

Abe has to balance Trump’s demands with the concerns of voters who believe overseas deployments violate the country’s commitment to pacifism enshrined in its post-World War II Constitution. With Sunday’s Takanami mission, Abe appears to have done just enough to avoid upsetting any parties.

Similarly, South Korea has announced that it would temporarily expand anti-piracy patrols by its Cheonghae naval unit to include the Strait of Hormuz and transfer troops already nearby in the region to the Persian Gulf.

“By operating outside the U.S. coalition, Japan and South Korea hope to minimize their military exposure while also preserving diplomatic ties and economic relations with Iran — something Prime Minister Abe has so far dexterously achieved,” Townshend said.