WASHINGTON D.C.: In a bid to create a much greater supply of Coronavirus vaccines, the White House has announced that Merck & Co. will assist in manufacturing the Johnson & Johnson one-shot vaccine.

The White House reportedly negotiated the assistance from Merck in the manufacturing of the vaccine.

White House Press Secretary Jen Psaki told reporters that an "across the administration effort" was needed to bring together the two rivals to work together on manufacturing the vaccine. She noted that conversations between officials of both companies had been ongoing for months.

"There's a difference between conversations and it moving forward," Psaki noted.

White House officials have said that Johnson & Johnson has only produced 3.9 million doses, thus far, because of undisclosed production issues.

However, Johnson & Johnson has committed to delivering 100 million doses by the end of June.

Psaki also said Tuesday that the federal government was increasing supplies of the Moderna and Pfizer vaccines to states next week, to reach a combined 15.2 million doses per week. Previously, the states have been sharing some 14.5 million doses weekly.

By the end of March, plans call for 16 to 17 million doses to be distributed weekly, with that number increasing to 17 to 18 million weekly doses by early April, said White House coronavirus coordinator Jeff Zients.

Regarding Johnson & Johnson being unable to reach its initial delivery commitment, company Vice President Richard Nettles testified before lawmakers in Washington last week, saying that the company had faced "significant challenges" because of its "highly complex" manufacturing process.

In comments about its participation in manufacturing vaccines, company officials said in a statement, "Merck remains steadfast in our commitment to contribute to the global response to the pandemic and to preparing to address future pandemics."