Asian shares hit 2013 lows; Nikkei slips as BOJ disappoints LONDON (Reuters) - The yen jumped against the dollar, shares sagged and German Bund prices followed Japanese bonds lower on Tuesday after the Bank of Japan disappointed investors by deciding not to implement further stimulus measures. Worries over slowing growth in China, the world's second-biggest economy, and the start of a hearing in Germany's top court about the legality of the European Central Bank's bond-buying scheme also kept investors in cautious mood. The dollar sank as low as 97.78 yen against the resurgent Japanese currency after Japan's central bank unnerved investors by not taking any action to curb a rise in government bond yields that threatens to thwart its stimulus efforts. "Many of the signals coming out of the BOJ recently have confused the markets, exacerbating volatility in bonds and hurting share markets," said Mike Ingram, market analyst at BGC Partners. The disappointment over the BOJ triggered further falls in Tokyo stocks, sending Japan's Nikkei index 1.5 percent lower .N225. MSCI's broadest index of Asia-Pacific shares outside Japan .MIAPJ0000PUS tumbled 1.1 percent to fresh 6-1/2-month lows. European shares .FTEU3 fell 0.7 percent in early trading as the BOJ's decision served to underline the reliance of investors on central banks to keep pumping money into the system. Some had expected the BOJ to extend the maximum duration of cheap fixed-rates funds. German Bund futures dropped 19 ticks to 142.66, tracking falls in Japanese bonds. Losses were seen capped as investors awaited a hearing over the legality of the European Central Bank's Outright Monetary Transactions (OMT) program in the German constitutional court. In commodity markets, oil and copper prices steadied with concerns over a slower pace of growth in top consumer China dragging on prices. Brent crude traded around $104 a barrel, while copper was near one-month low at $7,114.50 a ton. Editing by John Stonestreet