US President Donald Trump says his administration will fast-track efforts to develop a coronavirus vaccine by year-end.
Trump announced the project at the White House on Friday.
He said the objective is to "finish developing and then to manufacture and distribute a proven coronavirus vaccine as fast as possible." He said, "We would love to see if we can do it prior to the end of the year."
The president boasted the effort is unlike anything the US has seen since the Manhattan project, referring to the World War Two program to build the first atomic bomb.
Trump pledged full financial support for vaccine development and to simplify procedures for regulatory approvals.
But scientists have expressed skepticism about the prospect. Most expect vaccine development to take until next year at the earliest.