WASHINGTON (NewsNation Now) —  President Joe Biden Tuesday announced the U.S. is on track to have enough COVID-19 vaccine doses for every adult by the end of May.

“About three weeks ago, we were able to say that we’ll have enough vaccine supply for adults by end of July. I’m pleased to announce today as a consequence of the stepped up process that we’ve ordered and just outlined, this country will have enough vaccine supply for every adult in America by the end of May. That’s progress,” said Biden.

Biden called the announcement that Merck and Co Inc will help make rival Johnson & Johnson’s single-shot COVID-19 vaccine in a partnership, an example of “good corporate citizenship.”

Biden also added that he would like to see enough vaccine doses for every educator and school worker to receive the first dose of the vaccine by the end of March. He said he would direct every state to prioritize educators for vaccination.

The U.S. government will invoke the Defense Production Act in order to equip Merck’s plants to be able to produce the J&J vaccine, according to Biden.

The president says he hopes life returns to normal by this time next year but encouraged Americans to continue following public health guidelines and remain vigilant until then.

Biden announced the partnership, along with the increased vaccine availability, in a speech about the ongoing coronavirus pandemic, which has claimed more than 510,000 lives across the country.

During the speech, Biden pulled out a paper listing the death total from the pandemic so far: “I carry this in my pocket. As of today, we’ve lost more than 511,839 Americans. As of today.”

The announcement comes as the White House looks to speed the production of the single-dose vaccine. Officials have said J&J faced unexpected production issues with its vaccine and produced only 3.9 million doses ahead of its receiving emergency use authorization on Saturday. The company says it is on pace to deliver 100 million doses by the end of June.

“As soon as we learned about the fact that Johnson and Johnson was behind in the manufacturing steps and efforts, we took steps to ensure we can expedite that and partner them with one of the world’s biggest manufacturers,” Psaki told a White House briefing Tuesday afternoon.

Psaki also announced Tuesday that the federal government was increasing the supply of vaccines to states next week to 15.2 million doses per week, up from 14.5 million previously. States will also receive 2.8 million doses of the J&J shot this week.

Under its contract, J&J was supposed to deliver 12 million doses by the end of February but had less than 4 million ready to ship when the vaccine was authorized on Saturday.

It expects to be able to deliver another 16 million doses by the end of the month – still well short of its previous commitments – but will not ship any next week. The company has said it will be able to provide the full 100 million doses it has agreed to supply by its original midyear deadline.

Facing questions about the company’s slipping delivery schedule, J&J Vice President Richard Nettles told lawmakers on Capitol Hill last week that the company had faced “significant challenges” because of its “highly complex” manufacturing process.

J&J’s vaccine substance is made in the United States at a plant operated by Emergent BioSolutions Inc, as well as in facilities in the Netherlands and India.

There are two U.S. factories — run by Catalent and Grand River Asceptic Manufacturing — where the vaccine is finished and put in vials. The company also has partners with fill-finish capacity in Spain, Italy, India and South Africa.

Merck’s collaboration with J&J comes after Merck scrapped development of its own COVID-19 vaccine candidates in January. The company said last month that it was in talks with governments and companies to potentially help with manufacturing of COVID-19 vaccines that have been authorized.

Merck will dedicate two U.S. facilities to Johnson & Johnson’s vaccine, according to the Washington Post report.

“Merck remains steadfast in our commitment to contribute to the global response to the pandemic,” the company said.

Johnson & Johnson did not immediately respond to a request for comment.

McKesson Corporation, the U.S. government’s partner for COVID-19 vaccine distribution, began shipping out Johnson & Johnson’s vaccine to states on Monday from its plant in Kentucky.

McKesson has four facilities that will be specifically dedicated to distributing J&J’s vaccine.

So far, Johnson & Johnson’s shot is the only one-dose coronavirus vaccine available in the U.S. It also doesn’t require the ultra-cold storage needed previously by the two-dose Pfizer and Moderna vaccines, officials said, making storage and distribution much easier.

The vaccine is said to be well-suited for homebound seniors, the homeless and others that would have trouble showing up for an appointment for a second dose.

The Associated Press and Reuters contributed to this report. Reporting by Reuters’ Manas Mishra, Michael Erman, and Nandita Bose along with AP’s Zeke Miller.