The Washington-based lender also revised its forecast for global economic expansion in 2018 and 2019 to 3.9%, both 0.2 percentage points higher than the October projections and stronger than its estimate of a revised 3.7% expansion rate for 2017.
The IMF expects, "more subdued growth prospects in South Africa, where growth is now expected to remain below 1% in 2018-19, as increased political uncertainty weighs on confidence and investment".
"An increase in trade barriers and regulatory realignments, in the context of these negotiations or elsewhere, would weigh on global investment and reduce production efficiency, exerting a drag on potential growth in advanced, emerging market, and developing economies", they said.
Britain, which will leave the European Union in March 2019, will be one of the few countries to miss out on stronger growth.
America's top trading partners will also see benefits, especially Canada and Mexico. The IMF said it was the "broadest synchronized global growth upsurge since 2010" when the world enjoyed a strong, but ultimately fleeting, snapback from the financial crisis.
The International Monetary Fund (IMF) on Monday raised its global growth forecast for 2018 and 2019 by 0.2 percentage point to 3.9 percent, due to increased global growth momentum and the expected impact of the recently approved USA tax policy changes.
Global economic activity continues to firm up with global output estimated to have grown by 3.7 percent in 2017, which is 0.1 percentage point faster than projected in the fall and ½ percentage point higher than in 2016, said IMF's World Economic Outlook Update.More news: Flu outbreak in Florida continues to grow
According to the report, which was released in Davos on Monday, world growth is expected to exceed 2% in 2018 and 2019.
The Office for National Statistics will reveal its preliminary estimate for growth in the final quarter of 2017, and also the full calendar year, on Friday.
"The growth forecast for Japan has been revised up for 2018 and 2019, reflecting upward revisions to external demand, the supplementary budget for 2018, and carryover from stronger-than-expected recent activity", the International Monetary Fund said.
At first glance, that was but a small change, but it was more notable when compared with the growth predicted for other large advanced economies.
However, the rosier outlook came with a major caveat for financial markets, which the International Monetary Fund warned could be at the risk of a confidence-shaking correction. 'Firstly, policy makers should use these circumstances to make the structural or fiscal reforms that are too hard to make in more difficult times, ' she said.
The current cyclical upswing provides an ideal opportunity for reforms.
However, the fund warns that exuberant financial markets could be due for a reversal.