Japan's biggest brokerage house, Nomura Holdings Inc., said Tuesday its group net profit in the April to June quarter plunged 69.9 percent from a year earlier to ¥19.86 billion due to decreased commissions.

Net revenue declined 14 percent to ¥370.84 billion as commissions fell following brisk trading backed by Prime Minister Shinzo Abe's economic policies in the spring of last year.

Daiwa Securities Group Inc. also reported a 40 percent fall in group net profit to ¥34.38 billion in the three-month period, also due to decreased commissions. Daiwa's net revenue dropped 21.1 percent to ¥122.49 billion.

While Nomura and Daiwa showed solid performance in asset management, Nomura's investment banking business was sluggish.

Nomura Chief Financial Officer Shigesuke Kashiwagi said at a news conference that the firm aims to strengthen its resilience to changes in the market environment while making efforts to cut system and real estate-related costs.