The benchmark Nikkei 225 index at the Tokyo Stock Exchange lost 175.19 points to 8,562.47 by the lunch break, after falling to the lowest point since April 2009. The broader Topix index of all first-section issues dropped 13.73 points or 1.82 percent to 741.97. Global markets suffered heavy losses on Friday after the shock resignation of the European Central Bank chief economist Juergen Stark, which signalled more turmoil in the eurozone. Stark, known as an anti-inflation hawk, was critical of the bank's controversial programme of buying bonds of heavily indebted countries such as Greece who find the markets closed to them. "Disagreements within the ECB are raising concerns that the debt problem resolution will be further delayed," said Yutaka Miura, senior technical analyst at Mizuho Securities. "Investors are also worried that a Greek default will weigh heavily on German and French banks," he told Dow Jones Newswires. Finance ministers and central bankers of the Group of Seven rich nations met in France on Friday. They vowed tough measures to get the global economy back on track but were short on detail and admitted the problems were so complex that a unified response was impossible. The euro hit 104.90 yen in early trade, its lowest level since July 2001, down from 107.66 yen Friday, amid concerns over a possible Greek debt default without a new tranche of a rescue package by the end of the month. Honda Motor plunged 3.45 percent to 2,266 yen with Sony down 2.95 percent at 1,511. Financial issues also plunged, with Mitsubishi UFJ Financial Group dropping 2.40 percent to 324 yen and Nomura Securities off 2.34 percent at 292. "On top of the abrupt departure of an ECB executive board member, the market is unsettled by the Greek government's vague comments on the debt rollover plan," said Hideyuki Ishiguro, a strategist at Okasan Securities. Auditors from the troika of lenders -- the European Union, ECB and International Monetary Fund -- are expected to return to Greece this week. They had left Greece earlier this month because of the government's lack of progress on deficit reduction. Greece was seeking authorisation of the next tranche of its 2010 bailout plan.