US economy will stay open even in second virus wave: Mnuchin

US Treasury Secretary Steven Mnuchin said Thursday there will be no more shutdowns to stop the coronavirus pandemic, even as the outbreak flares in some states.

"We can't shut down the economy. I think we've learned that if you shut down the economy, you're going to create more damage," Mnuchin said in an interview on CNBC.

His comments were echoed by President Donald Trump, who tweeted "We will have a very good Third Quarter, a great Fourth Quarter, and one of our best ever years in 2021. We will also soon have a Vaccine & Therapeutics/Cure. That's my opinion. WATCH!"

The president's tweet came after the Federal Reserve on Thursday predicted an economic contraction of 6.5 percent this year, while warning the outlook remained uncertain.

"The Federal Reserve is wrong so often," Trump said. "I see the numbers also, and do MUCH better than they do."

Orders to close businesses to stop the virus's spread beginning in mid-March have badly harmed the world's largest economy, leading to tens of millions of layoffs and an unemployment rate of 13.3 percent in May, a figure reminiscent of the Great Depression 90 years ago.

Yet the virus remains deadly across the United States, with more than 112,900 deaths reported as of Wednesday and two million cases, while some states like Texas and North Carolina are seeing more hospitalizations from COVID-19 than they did a month ago.

Wall Street stocks reversed days of gains on Thursday, with major indices plunging into the red after the Labor Department reported another 1.5 million people filed new claims for unemployment benefits last week.