The International Monetary Fund has bumped up its forecasts for global growth, saying an upswing in the world economy was likely to gather pace into next year. 

Global economic output should increase by 3.6% this year and by 3.7%in 2018, up marginally from the forecast published six months ago but well above growth seen in 2016, the IMF said. 

But the global crisis lender called on governments to strike while the iron is hot, saying dangers for the current recovery lurked on the horizon and ambitious reforms were necessary. 

The new forecast comes as the IMF stages annual meetings this week with the World Bank.

On Ireland, the IMF said the economy would grow by 4.1% this year and 3.4% in 2018. That is an improvement on its previous forecasts of 3.5% and 3.2%

The IMF also upgraded its euro zone growth forecast despite Brexit uncertainty.

But it warned that low inflation, heavy debt and an ageing population could hurt the economy's recovery down the road. 

The IMF said the euro zone would reach 2.1% expansion in 2017 and growth would then slow to a still healthy 1.9% in 2018. 

This was an improvement from the previous estimate of 1.9% for 2017 and 1.7% in 2018.

The US also saw its economic forecast raised, but the IMF warned the coming years would likely see sluggish gains in the absence of growth-oriented policy from Washington. 

Citing strong market confidence in the world's largest economy, the global crisis lender said US GDP was now expected to grow by 2.2% this year, up a tenth of a percentage point from a forecast published three months ago. 

The US economy will also likely expand by 2.3% in 2018. 

The rosier outlook was based in part on a recovery in the energy sector and growing business investments earlier in the year.  

But the IMF said that - absent reforms and stimulus and with a Republican economic agenda suffering lengthy delays in Congress - the US was unlikely to sustain this pace.

The Fund also raised its growth forecast for China but again warned of risks stemming from the build-up of debt in the world's second largest economy. 

China is now expected to post 6.8% growth in 2017 and 6.5% next year, up from previous projections of 6.7% and 6.4% respectively.