In its latest outlook, released Monday, IMF economic counsellor Maury Obstfeld said global output could be 0.5 percent below current projections by 2020 if threatened tariffs materialised and business investment falls as a result.

The IMF left unchanged its global economic growth forecast of 3.9 per cent for both this year and next year. Forecasts for the US and China were both unchanged, with US growth pegged at 2.9 per cent this year and 2.7 per cent next year. China's growth forecast was 6.6 per cent this year and 6.4 per cent next year. But the fund cut its 2018 growth forecasts for eurozone countries and for Japan and Britain, citing a softer-than-expected first-quarter performance coupled with tighter financial conditions partly due to political uncertainty.