Nikkei falls 1.5 pct, caution rules ahead of data

(Updates to midsession)

TOKYO, March 31 (Reuters) - Japan's Nikkei average fell 1.5 percent on Monday, with investors locking in profits following last week's sharp gains and before a raft of key economic data.

Financial shares were under selling pressure, with Japan's third-largest bank Mizuho Financial Group (8411.T: Quote, Profile, Research, Stock Buzz) down 3.1 percent, after their U.S. peers fell on concerns about potential dividend cuts.

Trading house Marubeni Corp (8002.T: Quote, Profile, Research, Stock Buzz) plunged more than 6 percent after it said its U.K. subsidiary had suffered losses amid the global credit market turmoil. Separately, Lehman Brothers (LEH.N: Quote, Profile, Research, Stock Buzz) said it planned to sue Marubeni for repayment over a case of suspected fraud. [ID:nSP279128]

The benchmark Nikkei ended the morning session down at 12,627.83. The broader TOPIX fell 1.8 percent to 1,221.23. (Reporting by Taiga Uranaka)