Speaking during remarks to a J.P. Morgan healthcare conference this week, Pfizer CEO Albert Bourla openly stated current vaccines the company developed for Wuhan coronavirus offer “limited, if any” protection against contracting current variants of the disease. He then encouraged booster shots.

The statement from Bourla comes as the Biden administration continues to justify vaccine mandates for federal workers, contractors and private businesses. The Supreme Court heard arguments about President Biden’s mandates for private companies and medical workers last week. A ruling is expected soon on the constitutionality of the mandates.

A number of people who have pointed out the waning efficacy of Pfizer’s vaccines, which Bourla touted last year as being “100 percent” effective against contracting or transmitting the virus, have been banned by social media companies.