Nomura is acquiring Macquarie Group's U.S. and European public asset management businesses for $1.8 billion, marking the Japanese investment bank's most ambitious expansion abroad since its failed purchase of Lehman Brothers' assets.

Nomura Holdings plans to buy Macquarie Group’s public asset management business in the U.S. and Europe for $1.8 billion in a bid to strengthen its investment management business.

Japanese investment bank Nomura is set to acquire the U.S. and European public asset management businesses of Macquarie Group (OTC:MQBKY) in a A$2.8 billion ($1.8 billion) deal, the firms announced Tuesday.