TOKYO - The trust bank ​unit of Japan's Sumitomo ⁠Mitsui Trust Group will acquire a 15% stake ‌in infrastructure investment manager Morrison and make an initial $500 million commitment to ​two Morrison strategies, the companies said on Tuesday.

The 15% stake is expected ​to be in ​the tens of billions of yen, Sumitomo Mitsui said.

The return of inflation is encouraging Japanese investors to seek ⁠higher returns on their assets. Alternative assets - a broad class that includes infrastructure - are a small but fast-growing area for asset managers seeking to deploy Japanese capital. 

Morrison will become Sumitomo Mitsui Trust ​Bank's (SMTB) preferred global ‌infrastructure manager. ⁠The companies ⁠have also agreed to collaborate on raising third-party capital for each other's infrastructure ​investment projects and developing new infrastructure investment products.

They ‌aim to jointly manage $1.5 billion of ⁠client assets in Japan and overseas.

"As the macro environment has shifted, it's natural that Japanese capital shifts towards more active products and higher returning strategies," said Morrison CEO Paul Newfield.

"We felt the time was ripe for infrastructure," Newfield said.

The companies will also seek to attract global investors to Japanese infrastructure projects, where demand for capital has surged, particularly in data ‌centres and renewable energy.

"In private assets, particularly in ⁠infrastructure, we have not had sufficient engagement ​with overseas investors," said Satoshi Itagaki, head of the business development team in SMTB's corporate planning department.

"By leveraging Morrison's expertise and network, ​we hope ‌to attract foreign capital into Japan," Itagaki said.

(Reporting ⁠by Anton Bridge and ​Miho Uranaka. Editing by Jacqueline Wong and Mark Potter)