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With only nine days to go, it's unlikely the U.S. will meet the original goal of having 20 million people vaccinated by the end of the year, members of the White House's Operation Warp Speed have said.

"The process of immunizations — shots in arms — is happening slower than we thought it would be," Moncef Slaoui, chief science adviser for Operation Warp Speed, said during a media briefing Wednesday.

The news came after President Donald Trump threw a wrench into the massive year-end spending and coronavirus relief bill, leaving the country on edge as the threat of a government shutdown and expiring Covid-19 protections loom over the holiday season.

If Trump doesn't sign the bill, it will likely delay Americans getting any checks, shut the government down and allow some other coronavirus relief programs to expire.

• Map of U.S. hot spots and worldwide Covid-19 cases.
• Tracking surges in states across the country this winter.
• Map of travel restrictions and which states have a mask mandate.
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