The International Monetary Fund predicted the world economy’s strongest upswing since 2011 will continue for the next two years, but warned the seeds of its demise may have already been planted.

The fund on Tuesday left its forecasts for global growth this year and next at the 3.9% it estimated in January and raised its outlook for the U.S. as Republican tax cuts take effect.

Beyond that horizon, it was more pessimistic, projecting global growth will fade as central banks tighten monetary policy, the U.S. fiscal stimulus subsides, and China’s gradual slowdown continues.

“Global growth is projected to soften beyond the next couple of years,” the IMF said in its latest World Economic Outlook report. “Once their output gaps close, most advanced economies are poised to return to potential growth rates well below pre-crisis averages, held back by aging populations and lackluster productivity.”

The IMF warned the expansion could be derailed if countries resort to tit-for-tat trade sanctions.

“The first shots in a potential trade war have now been fired,” IMF Chief Economist Maurice Obstfeld said in a foreword to the fund’s outlook, reiterating the IMF’s warning earlier this month that the global trading order is in danger of being “torn apart.”

“Conflict could intensify if fiscal policies in the United States drive its trade deficit higher without action in Europe and Asia to reduce surpluses,” he said.

Investors with $543 billion of assets are the least optimistic about global growth momentum since the U.K. voted to leave the European Union, according to Bank of America Merrill Lynch. Just 5% of money managers project the international economy to be stronger in the next 12 months, the lowest level since June 2016, according to the bank’s April survey. Underscoring diminished growth momentum, earnings expectations have peaked.

Good Times

Governments should take advantage of the good times to make structural reforms and put in place tax policies that raise the potential output of their economies, Obstfeld said.

The IMF outlook is a reality check for finance ministers and central bankers from its 189 member countries as they gather this week in Washington for the fund’s annual spring meetings. President Donald Trump’s war of words with China over trade will be front and center. The U.S. has threatened to slap tariffs on as much as $150 billion in Chinese goods, while Beijing has vowed to retaliate in kind.

But the guardians of the global economy face challenges beyond trade, including the end of years of easy central-bank money and a world debt pile that has climbed to a record $164 trillion. Financial markets have been choppy this year, with U.S. stocks down slightly after a strong performance in 2017.

Broad Recovery

Globally, growth is being driven by a surge in business spending and a recovery in trade volumes, according to the IMF. Last year, the expansion covered two-thirds of countries, accounting for three-quarters of global output, making it the broadest upswing since 2010 when the world was coming out of the financial crisis.

But there are signs the synchronized recovery may be becoming a little more uneven, at least in the short term, with the U.S. charging ahead, fueled by tax cuts and government spending.

The U.S. economy will grow 2.9% this year, the IMF said, up 0.2 percentage point from the fund’s forecast in January. The U.S. will expand at a 2.7% pace next year, also up 0.2 point from three months ago.

The IMF’s revised U.S. forecasts includes the benefits of the tax cuts passed in December, as well as a $1.3 trillion spending bill. However, the fund said growth will be lower than expected after 2022, due to the higher budget deficit and the expiry of fiscal stimulus.

Faster Growth

The IMF also raised its forecast for the euro area, predicting the currency zone will grow 2.4% in 2018, up 0.2 point from January. The fund left its forecast for euro-zone growth next year unchanged, at 2%.

China will grow 6.6% this year and 6.4% in 2019, the fund said. Both forecasts were unchanged from three months ago.

The world’s second-biggest economy will continue re-balancing away from investment and manufacturing toward consumption and services, the IMF said, warning that rising debt clouds the nation’s medium-term outlook.

The IMF also left its outlook for Japan flat, predicting the nation will expand at a 1.2% pace this year and 0.9% in 2019.

India will grow 7.4% this year and 7.8% in 2019, both unchanged from January.

The fund cut its forecast for Canada to 2.1% this year, down 0.2 point from three months ago. The IMF also lowered its outlook for the Middle East and North Africa this year by 0.2 point, to 3.2%.

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