President Joe Biden said the US expects to take delivery of enough coronavirus disease 2019 vaccines for all adults by the end of May — two months earlier than anticipated — and he pushed states to get at least one shot into the arms of teachers by the end of March to hasten school reopenings.

Biden also announced Tuesday that drugmaker Merck will help produce rival Johnson & Johnson’s newly approved one-shot vaccine, likening the partnership between the two drug companies to the spirit of national cooperation during World War II.

“We’re now on track to have enough vaccine supply for every adult in America by the end of May,” Biden said.

Despite the stepped-up pace of vaccine production, the work of inoculating Americans could extend well into the summer, officials said, depending both on the government’s capacity to deliver doses and Americans’ willingness to roll up their sleeves.

Biden’s announcements quickly raised expectations for when the nation could safely emerge from the pandemic with the promise of speedier vaccinations, but even as he expressed optimism, Biden quickly tempered the outlook for a return to life as it was before the virus hit.

“I’ve been cautioned not to give an answer to that because we don’t know for sure,” Biden said, before saying his hope for a return to normal was sometime before “this time next year.”

As Biden spoke, states across the country were moving to relax virus-related restrictions. This despite the objections of the White House and the nation’s top infectious disease expert, Dr. Anthony Fauci, who have warned against any relaxation of virus protocols until more Americans are vaccinated.

In Texas, GOP Gov. Greg Abbott moved to lift his state’s mask-wearing mandate and a host of other limitations. Michigan’s Democratic Gov. Gretchen Whitmer eased capacity limits on restaurants and both public and residential gatherings.

Fauci has previously said the nation must achieve a vaccination rate of about 80 percent to reach “herd immunity.” Only about 8 percent of the population has been fully vaccinated, according to the Centers for Disease Control and Prevention, though the pace of vaccination has been increasing. The US set a new daily record for injections last Thursday and Friday.

In hopes of increasing vaccinations even further, the Biden administration told governors to make preparations to administer even more doses in the coming weeks. More shots are also headed toward the federally backed program to administer doses in retail pharmacies, which federal officials believe can double or triple their pace of vaccination.