* Euro edges higher vs dollar, yen after BOJ's stimulus plan

* Euro zone PPI down 1.3 pct, German retail sales fall

* Aussie dollar higher after RBA cuts rates 100 bps

* Investors wary ahead of ECB rate decision Thursday (Recasts, adds comments, changes byline and dateline, previous LONDON)

By Vivianne Rodrigues

NEW YORK, Feb 3 (Reuters) - The euro inched higher against the dollar and the yen on Tuesday after a Japanese stimulus plan briefly lifted sentiment, but investors remained wary of taking on risk.

Gains in the euro were limited as many in the market stayed sidelined ahead of the European Central Bank's rate decision on Thursday, where it is widely expected to leave interest rates on hold at 2 percent.

The Bank of Japan announced overnight a plan to buy up to 1 trillion yen in shares held by Japanese banks, which initially stirred hopes for a recovery in shares and an easing in risk aversion, but investors soon questioned its effectiveness.

"The Bank of Japan's announcement had only limited impact," said Marc Chandler, a currency strategist at Brown Brothers Harriman in New York. "Markets remained concerned about the deteriorating global economic environment."