The number of confirmed U.S. coronavirus cases neared 1 million on Tuesday and the projected American death toll rose in a closely watched academic model, even as some states eased restrictions aimed at fighting the pandemic battering the economy.

With President Donald Trump's economic adviser forecasting an unemployment rate of more than 16% for April and many Americans chafing under stay-at-home orders, about a dozen states were moving to restart their battered economies despite a lack of large-scale virus testing.

Public health experts have warned that a premature rollback of social distancing policies aimed at curbing the spread of the pathogen could cause a surge in new infections.

Georgia, at the vanguard of states reopening businesses, on Monday permitted restaurant dining for the first time in a month. Texas Governor Greg Abbott said on Monday he would let the state's stay-at-home order expire and begin reopening businesses including restaurants and retail shops in phases beginning on Friday.

The governors of other states including hard-hit New York have put off the reopening of businesses out of concern they might fuel a second wave of infections.

The U.S. Chamber of Commerce, the top lobbying group for the nation's business sector, called for consistency across federal, state and local governments to reopen the economy but urged against any public health guidelines becoming regulations that could harm businesses as they seek to restart.

The number of confirmed U.S. coronavirus infections - just shy of 1 million - has doubled in 18 days and comprises a third of all reported infections globally. The actual number of U.S. infections is believed to be higher than the confirmed number of cases, with state public health officials cautioning that shortages of trained workers and materials have limited testing capacity, leaving many infections unrecorded.

More than 56,000 Americans have died of COVID-19, the respiratory illness caused by the virus, with an average of about 2,000 a day this month, according to a Reuters tally.

Squadrons of U.S. Navy Blue Angels jets and U.S. Air Force Thunderbirds jets were scheduled to perform joint flyovers in the sky above New York, New Jersey and Pennsylvania in a tribute to frontline responders and essential workers fighting the pandemic. Officials behind the flyovers encouraged residents to watch while practicing social distancing.