The Food and Drug Administration on Friday authorised the coronavirus vaccine made by Moderna for emergency use, allowing the shipment of millions more doses across the nation and intensifying the debate over who will be next in line to get inoculated.

The move will make Moderna’s vaccine the second to reach the American public, after the one by Pfizer and BioNTech, which was authorised just one week ago.

The FDA’s decision sets the stage for a weekend spectacle of trucks rolling out as expert committees begin a new round of discussions weighing whether the next wave of vaccinations should go to essential workers, or to people 65 and older, and people with conditions that increase their risk of becoming severely ill from Covid-19.

Jockeying for the next shots in January and February has already begun, even though there is still not enough of the two vaccines for all the healthcare workers and nursing home staffers and residents given first priority.

Uber drivers, restaurant employees, morticians and barbers are among those lobbying states to include them in the next round along with those in the more traditional categories of the nation’s 80 million essential workers.