U.S. President Joe Biden. (Getty/Kyodo)

U.S. President Joe Biden tested negative for the novel coronavirus for a second consecutive day on Sunday and will end his isolation, his physician said.

The 79-year-old initially tested positive on July 21 and experienced mild symptoms. He then returned negative test results before testing positive again from July 30 in what was classed a "rebound" case, seen in some people who take the antiviral drug Paxlovid.

Biden tested negative Saturday morning and again Sunday morning. "He will safely return to public engagement and presidential travel," the doctor, Kevin O'Connor, said.

The president has been fully vaccinated and received two booster shots for additional protection.

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