TOKYO — Nomura Holdings, the scandal-hit Japanese investment bank, outlined a broad reorganization plan Thursday that would pare back its business to a shadow of what it held after acquiring parts of Lehman Brothers in 2008.

Most of the $1 billion in cuts will be made abroad. They are driven by a grim outlook for the global economy, Koji Nagai, Nomura’s new chief executive, told analysts and investors at the company’s headquarters in Tokyo.

Nomura’s operations in Europe, which will account for 45 percent of the cost savings, and the Americas, which will account for 21 percent, will take the brunt of the cutbacks, the bank said.

Although Nagai declined to specify the number of jobs that Nomura would eliminate, the company said it would shave $450 million from personnel expenses. Other cuts would come from savings from information technology, the bank said.