HONG KONG shares endured a torrid five days' trading last week, as the relentless slide of the Japanese yen sent shockwaves through the region's financial markets, brokers said. The Hang Seng Index dropped through the 8,000-point level to its lowest close in more than three years, shedding 7.63 per cent to finish at 7,915.44 points. Mainland-related plays were also in the firing line, as fears flared about the medium-term stability of the yuan. These fears gathered pace on Tuesday and Wednesday after People's Bank of China governor Dai Xianglong warned that the slide of the Japanese currency was harming the mainland's trade performance. Using direct language, he urged Tokyo authorities to stem the yen's slip against the US dollar. 'The depreciation of the Japanese yen is having a very negative impact on Chinese imports and exports and the utilisation of foreign capital,' he said. The Japanese currency, which started the week at about 139 to the US dollar, went into the weekend at about the 144 level. Brokers said its fall had re-ignited concern that a second wave of currency depreciations would swamp the region, jacking up pressure against the currency-board system. With interbank rates hitting five-month highs, investors sold into a falling market, its descent accelerated by large short positions held by international investors. Over the week, the red-chip index shed 17.53 per cent to end at 881.83 points, while the H-share measure dropped 14.68 per cent to 431.06 points. The market's declines - the worst of which was seen midweek, when the blue-chip measure lost 412.09 points - provoked the usual response from officialdom. Chief Executive Tung Chee-hwa vowed the peg would endure, blamed the latest turmoil on external factors and said Government funds would not be used in support of share prices. More practically, the Hong Kong Monetary Authority (HKMA) on Thursday said it would move to frustrate currency speculators by issuing more timely information on liquidity in the interbank market. 'The more transparency in the interbank market, the more difficult for currency speculators to attack the Hong Kong dollar,' HKMA Chief Executive Joseph Yam Chi-kwong said. Japanese concerns again dominated on the final day of trade, with the release of first-quarter figures showing Japan's economy had tumbled into recession. Short-covering helped the Hang Seng Index hold its ground ahead of the weekend, but brokers said the news undermined prospects for the region's economic recovery. Lehman Brothers global chief economist John Llewellyn told clients: 'Asia, with Japan at the epicentre, is already destabilising many emerging markets. With no sign that Japan is coming to grips with its problems, this destabilisation seems set to intensify and widen. [It's] time to batten the hatches.'