Washington ? From the United States to Europe and even to booming China, the global economy is showing signs of strain.

Most major economies are expected to keep growing. But evidence is mounting that many around the world are struggling to expand as fast as they did last year.

European governments are struggling with debts and squeezed budgets. Britain’s economy scarcely grew at the start of the year. Even Europe’s strongest economy, Germany, may face a slowdown.

High unemployment, depressed real estate and still-high oil prices are slowing the U.S. economy, which grew at a scant 1.8 percent annual rate from January through March. And after its earthquake and nuclear crisis, Japan has sunk back into a recession.

In China, interest-rate hikes designed to reduce inflation are slowing growth.

Overall, the world economy will likely grow just 3.5 percent this year, down from 4.1 percent in 2010, according to the research firm IHS Global Insight. IHS has cut that forecast from 3.8 percent.

As leaders of the Group of Eight rich democracies meet in Paris, slowing global growth is on an agenda already packed with concerns about instability in the Middle East, Greece’s debt crisis and who will be the next head of the International Monetary Fund. It isn’t a priority item at the meeting, though.

“The eurozone is a big mess, and the Europeans don’t want to talk about it,” said Simon Johnson, a former chief economist of the IMF.

The most serious such problems exist in Greece, Spain, Portugal and Ireland, which are overwhelmed with debts run up during the financial crisis and the recession that followed.

Financial markets have been signaling concerns about a worldwide slowdown. The Dow Jones industrial average has shed 450 points, or 3.5 percent, this month. Stocks have slid 3 percent or more this month in Japan, Britain and Hong Kong.