Former New Jersey Gov. Chris Christie (R) on Sunday said the new federal vaccine mandate that President Biden announced last week will “harden opposition” to getting inoculated.

“This is going to harden opposition. Sometimes when you’re a leader, you have to go in and use a sledgehammer. And I’ve been known to do that when I was governor. Sometimes it’s appropriate, but this one was not the time to do it. We have to be persuasive, we have to continue to persuade,” Christie said during an appearance on ABC’s “This Week.”

Christie’s comments come after Biden on Thursday unveiled a new federal vaccine rule that will require private businesses with 100 or more employees to mandate vaccines or weekly testing.

The rule, which could impact almost 80 million workers, will be issued by the Department of Labor’s Occupational Safety and Health Administration (OSHA) in the coming weeks.

Christie said on Sunday that the Biden administration is on “shaky legal grounds” regarding whether or not the vaccine mandate can be enforced because of the OSHA statutes being used.

The former New Jersey governor also argued that mandating vaccines for federal workers is “contradictory” because health officials have said that inoculated individuals are well protected from unvaccinated individuals.

“Working for the government and ordering government workers to have to have a mandate there’s one thing, extending that to two-thirds of all the jobs and making it either give vaccine or not, it’s also contradictory logically,” Christie told host George Stephanopoulos.

“Because what they’re telling us is, by all the data, that vaccinated people are very, very well protected from anyone who’s unvaccinated and who has it, yet they’re saying to us, we have to do this to protect you. Well, that’s protecting the unvaccinated from the unvaccinated,” he added.

“Sometimes, when you’re a leader, you have to go in and use a sledgehammer … But this one was not the time to do it.” @GovChristie tells @GStephanopoulos that Pres. Biden’s new COVID-19 vaccine mandates for companies will “harden opposition.” https://t.co/v81ip0pEQk pic.twitter.com/WnjVvIthmJ

— This Week (@ThisWeekABC) September 12, 2021

Christie has been supportive of the COVID-19 vaccine, saying during a television appearance in July “the vaccines do work.”

Christie tested positive for COVID-19 in October and was hospitalized after attending debate preparation sessions with then-President Trump at the White House. He later said he was wrong for not wearing a mask on the White House grounds.