Japan's economy will contract 4.7 percent in the year to March 2021, the central bank said Wednesday, projecting a recovery the following year but warning that deep uncertainty remains.

The fresh outlook, with policymakers giving a range of contraction from 5.7 to 4.5 percent, is a downgrade from an April range of between 5.0 percent and 3.0 percent.

The Bank of Japan was hopeful of a future recovery but said the outlook was shrouded by possible future waves of the virus, which made calculations difficult.

"Japan's economy is likely to improve gradually from the second half of this year with economic activity resuming, but the pace is expected to be only moderate while the impact of the novel coronavirus remains worldwide," the BoJ said in a statement.

The bank said it expected the global economy to recover steadily, projecting Japanese GDP would expand 3.3 percent in the year to March 2022, before logging 1.5 percent growth in the following fiscal year.

But it also stressed that "the outlook... is extremely unclear" with its assumptions involving "high uncertainties".

Japan's economy will contract 4.7 percent in the year to March 2021, its central bank says
Japan's economy will contract 4.7 percent in the year to March 2021, its central bank says AFP / CHARLY TRIBALLEAU

Capital investment is relatively solid, but consumption remains low particularly in the services sector that requires face-to-face interactions, BoJ Governor Haruhiko Kuroda told reporters.

"Overall, there is no doubt that the economy is bottoming out and is on a recovery phase," Kuroda said.

"But after this, the speed (of recovery) will slow and I expect that we will see a gradual recovery."

Officials also see Japan's core consumer prices falling 0.5 percent for the year to March, well below the government's target of stable 2.0 percent inflation to foster sustainable growth.

The central bank said it would maintain its massive monetary easing programme, leaving short-term rates at minus 0.1 percent while keeping long-term rates around zero percent.

"We will take additional easing measures with no hesitation if necessary," Kuroda pledged.