Prime Minister Shinzo Abe plans to promote cooperation in China’s cross-border infrastructure development project, in a shift in diplomatic policy to check Beijing’s growing territorial assertiveness in the region, government sources said Sunday.

The Japanese government has briefed China on Abe’s current goal of promoting a free and open Indo-Pacific region and the policy’s positive effects on Beijing’s so-called One Belt, One Road cross-border infrastructure initiative, according to the sources.

“Our strategy is to achieve stability and prosperity of international society by coordinating with countries in the Indian Ocean and Pacific Ocean,” one of the sources said. “This should contribute to advancing the One Belt, One Road initiative.”

Since the two countries’ policies have overlapping areas, Japan is considering supporting joint infrastructure development and business promotion by companies of the two nations, the sources said.

Abe believes it is imperative for Japan to improve its diplomatic relationship with China, given its increasing presence in the global economy and security, the sources said.

The prime minister now aims to work on achieving a free and open Indo-Pacific and cooperate in advancing Beijing’s One Belt, One Road infrastructure initiative at the same time. Japan is also looking to realize an early visit by Chinese President Xi Jinping to Japan.

Abe unveiled the Indo-Pacific policy in August last year apparently to keep China’s growing maritime assertiveness in the East and South China seas in check by stressing the importance of realizing maritime order based on the rule of law.

He has argued that a “free and open” maritime order is critically important for the peace and prosperity in the Indo-Pacific region, which covers the vast area of the Asia-Pacific, and through the Indian Ocean to the Middle East and Africa.

Under the initiative, Tokyo plans to support the development of countries that share the same idea in the region.

The Chinese president unveiled his One Belt, One Road policy initiative in 2013. Under the initiative, China aims to build a new “Silk Road” to expand trade and infrastructure networks in Asia, the Middle East, Europe and Africa.

Abe said in a speech in Tokyo earlier in the month, “I believe Japan will be able to cooperate well with China, which has been putting forward its One Belt, One Road initiative, while we are pursuing a strategy to achieve a free and open Indo-Pacific region.”

Still, with the policy shift, Abe’s government will need to ensure consistency with its current diplomatic and security policies involving its alliance with the United States and defense cooperation with Britain and Australia.

Some officials of the Foreign and Defense ministries are concerned about Tokyo’s shift to take a more conciliatory line toward China by putting priorities on the envisioned economic benefits, the sources said.