The world economy is expected to contract by 5.2 percent this year - the worst recession in 80 years - but the sheer number of countries suffering economic losses means the scale of the downturn is worse than any recession in 150 years, the World Bank said in its latest Global Economic Prospects report.

"This is a deeply sobering outlook, with the crisis likely to leave long-lasting scars and pose major global challenges," said World Bank Group Vice President for Equitable Growth, Finance and Institutions Ceyla Pazarbasioglu.

The depth of the crisis will drive 70 to 100 million people into extreme poverty - worse than the prior estimate of 60 million, she told reporters. Economists have been struggling to measure the impact of the crisis they have likened to a global natural disaster, but the sheer size of the impact across so many sectors and countries has made that difficult.