By Natsuko Waki

LONDON (Reuters) - World stocks hit their lowest level in almost two years on Tuesday as a worsening German business mood and fresh concerns about financial firms triggered a sell-off in risky assets, lifting the dollar to a 2008 high.

The Munich-based Ifo economic research institute's business climate index fell to 94.8 this month from 97.5 in July, below the 97.1 forecast, adding to evidence that growth outside the United States is slowing and accelerating the euro's tumble.

"This does not bode well for the second half of the year. The probability of a recession has risen," said Antje Hansen, economist at HSBC Trinkaus.

The FTSEurofirst 300 index fell 0.6 percent while the MSCI main world equity index lost as much as 1 percent to its lowest since September 2006, bringing year-to-date losses to more than 18 percent.

However, U.S. stock futures rose a quarter percent, pointing to a firmer open on Wall Street after major indexes fell 2 percent on Monday.

The September Bund future was up 17 ticks, while euro zone interest rate futures also firmed as investors priced in an interest rate cut in the region.

Investors have been deluged with grim news from the financial sector this week.

JP Morgan has said the market value of its investments in preferred stock of U.S. mortgage lenders Fannie Mae and Freddie Mac has halved this quarter.