The Organization for Economic Cooperation and Development (OECD) released its growth forecast on Wednesday. The OECD kept its global growth outlook unchanged.

"Growth is flat in the advanced economies and has slowed in many of the emerging economies that have been the global locomotive since the crisis," the OECD Secretary-General Angel Gurria.

"Slower productivity growth and rising inequality pose further challenges," he added

The OECD expect the U.S. will grow 1.8% in 2016, down from the previous estimate of 2.0%, and 2.2% in 2017, unchanged from the previous estimate.

Japan's economy is expected to grow 0.7% in 2016 and 0.4% in 2017, down from the previous estimates of 0.8% and 0.6%, respectively.

Eurozone's forecast was upgraded to 1.6% in 2016 from the previous estimate of 1.4%, while 2017 forecast remained unchanged at 1.7% in 2017.

The OECD noted that Britain's leave from the European Union would weigh on the economic growth in the U.K., other European countries and the rest of the world.

China is expected to expand at 6.5% in 2016 and 6.2% in 2017, unchanged from the previous estimates.

Global GDP is estimated to grow 3.0% in 2016 and 3.3% in 2017, unchanged from the previous estimates.