The benchmark Nikkei index at the Tokyo Stock Exchange fell 195.10 points to close at 8,640.42. The Topix index of all first-section issues lost 15.92 points, or 2.11 percent, to 738.58. "The Greek public doesn't like the bailout package involving austerity measures. Optimism ahead of the G20 meeting (on Thursday) has melted away," said Fumiyuki Nakanishi, general manager of investment and research at SMBC Friend Securities. Tsuyoshi Segawa, equity strategist at Mizuho Securities, said the key event to watch is the upcoming parliamentary vote of confidence in the Greek government on Friday. "It remains unclear what is going to happen in Europe," Segawa told Dow Jones Newswires. The eurozone was plunged back into a fresh crisis and markets were sent into a panic on Tuesday when Greek Prime Minister George Papandreou called a surprise referendum on the hard-won debt rescue package agreed last week. Japanese Finance Minister Jun Azumi said Wednesday the referendum plan had "confused people". The Group of 20 advanced and developing nations will discuss the issue when they start a meeting in France on Thursday, Azumi told reporters. US stocks dived Tuesday, with the blue-chip Dow Jones Industrial Average losing 2.48 percent to finish at 11,657.96 after sharp falls in Europe. The euro was at $1.3741 in Tokyo afternoon trade, up from $1.3609 in New York late Tuesday. It firmed to 107.33 yen from 107.29. The euro rose into the $1.42 level last week after a summit of European leaders reached a comprehensive deal to resolve the months-long crisis, starting with a new Greek debt reduction and austerity deal. The dollar edged down to 78.10 yen from 78.34 yen. Nomura Holdings tumbled 4.08 percent to 282 yen after the company posted its first loss in more than two years in the July-September period as the impact of market turbulence and the eurozone crisis hit hard. Hitachi fell 2.34 percent to 416 yen after its July-September net profit fell 33 percent on-year.