Pfizer Inc. pushed back on claims it is experiencing problems producing its Covid-19 vaccine, as the company and the federal government continued to try to reach a deal that would eventually double the number of doses available for the U.S.’s vast immunization effort. Moncef Slaoui, the chief scientific adviser to Operation Warp Speed, said in an interview on Thursday that the U.S. is close to a deal for another 100 million doses of the vaccine Pfizer developed in partnership with BioNTech SE. Through the agreement, Pfizer would deliver the additional supply in the second quarter of 2021, Slaoui said. In July, Operation Warp Speed, the U.S. vaccine-development program, agreed to buy 100 million doses of the two-dose regimen; the $1.95 billion contract came with an option to buy 500 million more doses. However, Pfizer and federal officials have been at odds after reports that the government declined a subsequent offer to buy more doses, and that Pfizer would need to fulfill commitments to other countries before it could get more stock to the U.S. The wrangling during the first week of the vaccine’s rollout came as other supply questions emerged. Some governors complained this week that their allocations of the vaccine are less than what they expected. Florida Governor Ron DeSantis said his state had a shortfall he blamed on what he said were production issues at Pfizer. Health and Human Services Secretary Alex Azar made similar claims in a briefing Wednesday. Subscribe to our YouTube channel: https://bit.ly/2TwO8Gm Bloomberg Quicktake brings you live global news and original shows spanning business, technology, politics and culture. Make sense of the stories changing your business and your world. To watch complete coverage on Bloomberg Quicktake 24/7, visit http://www.bloomberg.com/qt/live, or watch on Apple TV, Roku, Samsung Smart TV, Fire TV and Android TV on the Bloomberg app. Have a story to tell? Fill out this survey for a chance to have it featured on Bloomberg Quicktake: https://cor.us/surveys/27AF30 Connect with us on… YouTube: https://www.youtube.com/user/Bloomberg Breaking News on YouTube: https://www.youtube.com/c/BloombergQuickTakeNews Twitter: https://twitter.com/quicktake Facebook: https://www.facebook.com/quicktake Instagram: https://www.instagram.com/quicktake