NASA on Wednesday asked its employees to work from home after two tested positive for coronavirus.

"This evening, NASA leadership has decided to elevate all centers and facilities to Stage 3 of NASA’s Response Framework. Effective immediately, all employees and contractors will move to mandatory telework until further notice," said NASA Administrator Jim Bridenstine in a statement.

"Mission-essential personnel will continue to be granted access onsite," he added. 

The expected decision came shortly after Ames Research Center in California and Marshall Space Flight Center in Alabama were designated as Stage 3 when two employees at the said facilities tested positive for COVID-19.

The last stage of NASA's Response Framework is Stage 4. A facility on Stage 4 will be shut down with few exceptional cases and all travels will be suspended.

In the U.S., the death toll from novel coronavirus has climbed to 150, with total confirmed cases over 9,400, according to Johns Hopkins University in Maryland.