The Americas will bear the brunt of an estimated 305 million job losses that the COVID-19 pandemic will cause worldwide between April and June, the International Labour Organization (ILO) said on Wednesday.

The outbreak also risks creating a "lockdown generation" of young people forced to play catch-up on the labor market for at least 10 years, the Geneva-based body said.

Its report left its estimate for second quarter job losses - calculated in terms of working hours compared to a pre-pandemic baseline - unchanged from a month ago.

The Americas, meanwhile, jumped from being the least affected region in labor market terms in the first quarter to being the most affected, with an expected 13.1 percent drop in working hours in the second, ILO Director-General, Guy Ryder, told a briefing.

That was due to it having become the outbreak's new epicenter.

The U.S. Labor Department's April employment report showed that the nation's unemployment rate has soared to 14.7 percent, with 20.5 million job loss.

Although 78 percent of Americans consider the laid-off to be temporary, another research suggests that for many people, the job lost can be permanent.

The University of Chicago's Becker Friedman Institute anticipates that 42 percent or 11.6 million job loss through April 25 due to the pandemic can become permanent.

"The current crisis may be so severe that the fraction of temporary layoffs that become permanent ends up being much larger than historical evidence would suggest," co-author Jose Maria Barrero told CNBC.

Ryder also said he was "extremely concerned" about young people who are being affected disproportionately by the crisis, saying this might lead to a "lockdown generation".

"Young people are simply going to be left behind, and in big numbers," he said.

"The danger is, that this initial shock to young people will last a decade or longer. It will affect the (employment) trajectory ... throughout their working lives."

More than one in six working people aged up 24 had lost their jobs since the start of the outbreak, the ILO said.

The organization also highlighted particular problems in the United States and Brazil.

It was "worrisome" that the U.S. labor market remained "difficult" while other countries easing lockdowns had started to see modest recoveries, said the director of its Employment Policy Department, Sangheon Lee.

In Brazil, there was "good reason to be concerned both about the trajectory of the pandemic and the capacity to put in place the right sort of (workplace) measures to react to it," Ryder said.

The ILO hiked its estimate of first quarter job losses by seven million to 135 million.

(With input from agencies)