The International Monetary Fund said Friday it expected the world economy to grow at a slower pace than previously expected, dampened by higher oil prices and sluggish factory output. The lending body also cautioned the European debt crisis poses a greater threat to the global economy, citing heightened investor concerns that the Greek government will not be able to make the changes necessary to avoid a default on its debt. It predicted the world economy will grow by 4.3 percent this year, down from its April forecast of 4.4 percent. But it remained optimistic about the Chinese economy, maintaining its prediction last month of 9.6 percent growth for 2011.