US President Joe Biden on Saturday said the approval of Johnson & Johnson's single-shot coronavirus vaccine by the US Food and Drug Administration (FDA) is "exciting news" but warned Americans against letting their guard down as the situation could deteriorate.

On Saturday, the FDA announced that it had approved the Janssen COVID-19 Vaccine for emergency use in the US in individuals 18 years of age and older. "This is exciting news for all Americans and an encouraging development in our efforts to bring an end to the crisis," Biden said in a Saturday statement.

"But I want to be clear: this fight is far from over. Though we celebrate today's news, I urge all Americans -- keep washing your hands, stay socially distanced, and keep wearing masks. As I have said many times, things are still likely to get worse again as new variants spread, and the current improvement could reverse," he added.

The FDA approved the nation's third coronavirus vaccine. The official emergency use authorization for Johnson & Johnson's (J&J) single-dose vaccine comes after an FDA advisory panel voted 22-0 to recommend authorization on Friday.

The United States has reported more than 28.5 million confirmed Covid-19 cases and over 511,000 reported deaths. The demand of vaccines still far exceeds supply, these vaccines can't come soon enough.

"A third safe and effective vaccine is very welcome news," Andy Slavitt, the White House's senior for Covid Response, tweeted on Friday.

The vaccine, made by Janssen, J&J's vaccine arm, is safe and effective, and it's considered flexible. It's a single dose, and it doesn't require special storage.
The vaccine is authorized for people ages 18 and older. (ANI)