The Nomura Securities Co. group is negotiating a tieup with U.S. investment bank Thomas Weisel Partners LLC, the Japanese brokerage said Monday.

"It is true that we are in talks, but nothing has been decided officially yet in the ongoing negotiations," Nomura Holdings Inc. said in a statement, referring to an earlier news report by a business daily.

The Nihon Keizai Shimbun reported Monday morning that the Nomura group has agreed in principle on a capital alliance with Thomas Weisel to jointly promote investment banking operations, chiefly in the promising business of backing up mergers and acquisitions by Japanese and U.S. companies.

The Nomura group is to invest 20 billion yen to take an equity stake in Thomas Weisel and contribute to its investment funds, the daily said.

Given the alliance, the Nomura group plans to beef up its consulting operations for Japanese companies eyeing mergers and acquisitions with U.S. partners, it said.