Reports suggest it now expects the economy to grow 2.4% this year – faster than any other major European economy – against its previous forecast of 1.9%.
This would bring its forecast in line with that of the UK’s Office for Budget Responsibility.
The IMF is also expected to raise its global growth outlook slightly to 3.7%.
The group’s managing director, Christine Lagarde, said earlier this month that the IMF would be upgrading its growth forecasts.
Ms Lagarde has previously expressed concerns about growth levels in the UK economy in light of the government’s austerity drive, which is designed to reduce debt levels.
On Monday, the EY Item Club of economists said it expected the UK economy to grow by 2.7% this year.
Confidence in the UK economy has increased markedly in recent weeks, with unemployment falling, the manufacturing sector and retail sales recording strong growth, and inflation back at the government’s 2% target rate.
Further evidence of the recovery came on Tuesday with publication of the CBI business group’s Industrial Trends Survey. This found that growth in new manufacturing orders was at its strongest since April 2011.
“The recovery in the manufacturing sector is continuing to build and confidence has improved,” said Stephen Gifford, the CBI’s director of economics.