Nouriel Roubini, the New York University economist credited with predicting the financial crisis, says government bonds of countries such as Germany, Canada and the United States will represent a haven from increasingly volatile markets in coming months.

“It is going to be a period of economic and financial fragility,” Roubini told Bloomberg in an interview in Aix en Provence, France.

“The short-term and long-term debt of countries not yet subject to sovereign debt concern will be havens,” he said.

The global economy will slow in the second half as deficit- reduction measures, notably in Europe, erode demand, Roubini told Bloomberg.

U.S. growth will ease to about 1.5 percent by the end of 2010, about half its potential, while the euro area’s expansion may stall and be “closer to zero,” he was quoted by Reuters as saying. The world should avoid a double-dip recession, he said.

"Given the shocks of the last few months ... by year-end, euro-zone growth could be closer to zero percent," said Roubini, who has been nicknamed "Doctor Doom" for his pessimistic forecasts.

He said his previous estimate of 1 percent was similar to forecasts by the European Central Bank and the International Monetary Fund.

The past three months' stock-market correction, rising credit spreads and a jittery inter-bank lending market suggested there were serious concerns over economic growth at a global level, Roubini told Reuters.

Growth in the U.S. economy could slow in the second half of this year to 1.5 percent from 3 percent in the first, he said.

"For the global economy, by year-end, the picture is not a very nice one," said Roubini.