TOKYO >> Japan is set to announce that it will approve the sale of advanced air defense systems to the United States, a significant shift in its postwar policies restricting the export of weapons and military hardware, and a move that could help Washington support Ukraine in its fight against Russia.

Prime Minister Fumio Kishida’s Cabinet is expected to meet Friday morning to discuss changes to Japan’s restrictions on weapons exports, a Japanese and an American official said, which would allow Tokyo to sell American-designed Patriot missiles made in Japan back to the U.S. government. Both officials spoke on condition of anonymity because they were not authorized to speak publicly about the timing of the announcement.

The move is another sign that Japan, a pacifist nation since the end of World War II, is taking on a larger global security role. Although the country’s export policies prevent it from selling lethal weapons “destined for a country party to a conflict,” a working group of the governing Liberal Democratic Party and its coalition partner, Komeito, has recommended changes that would authorize sales of equipment made under license back to the countries where the original manufacturers are based.

Mitsubishi Heavy Industries makes the Patriot missiles, which can be used to shoot down drones and warplanes, under a license from American manufacturers Raytheon and Lockheed Martin. So far, Mitsubishi has made the air defense systems for Japan’s military.

If Japan exports the Patriot systems back to the United States, the “side benefit is it obviously gives us some flexibility with our worldwide inventory and obligations,” said Rahm Emanuel, the U.S. ambassador to Japan, speaking about the anticipated announcement. The United States approved the shipment of Patriot missiles to Ukraine late last year.

The Washington Post reported the planned export of Patriot missiles earlier this week.

Emanuel said the expected change in Japanese export policy added to already announced measures by Tokyo to raise military spending to 2% of gross domestic product, or by about 60%, over the next five years. Japan has also accelerated its spending on Tomahawk missiles from the United States and moved up the first delivery date for those weapons to 2025, from 2026. Tomahawk missiles are capable of striking targets in enemy territory.

“The pace of reforms and the significance of the reforms are unprecedented and incredibly welcomed,” Emanuel said.

Japan’s government is also discussing the possibility of sending artillery shells to the United States, said a Japanese official, who spoke on the condition of anonymity because he was not authorized to speak publicly. The United States has repeatedly asked allies to help bolster stockpiles and send ammunition to Ukraine, but Japan’s export restrictions have so far prevented it from doing so.

The government is also expected to discuss policy changes to allow it to export a fighter jet that Japan is jointly developing with Britain and Italy. When the three countries signed an agreement in Tokyo last week to develop the jet, Grant Shapps, the British defense minister, said that without Japan agreeing to allow sales of the jet to third parties, “Who will be able to take the project forward at all?”

In comments to reporters last week, Yoshimasa Hayashi, the chief Cabinet secretary, said the Japanese government hoped to further revise its export restrictions to allow for the sale to third countries of weapons “developed through international joint projects.”

This article originally appeared in The New York Times.