Arkansas Gov. Asa Hutchinson said President Joe Biden’s order that private businesses require employees to be vaccinated against COVID-19 is not the right answer for boosting vaccination rates.

Meanwhile, Hutchinson’s counterpart in Mississippi and Montana slammed the mandate plan.

Said Hutchinson: “I have been consistent in the freedom of businesses to require their employees to be vaccinated, and I have opposed the government from saying businesses cannot exercise that freedom.”

The Republican, who chairs the National Governors Association, added in a statement. “The same principle should protect the private sector from government overreach that requires them to vaccinate all employees.”

Some of Arkansas’ largest employers are already requiring workers to get vaccinated.

Meanwhile, in Montana, Gov. Greg Gianforte is calling a new vaccination mandate that could affect as many as 100 million Americans “unlawful and un-American.”

Gianforte, a Republican, said in a tweet on Thursday that he is “committed to protecting Montanans’ freedoms and liberties against this gross federal overreach.”

Montana is the only state in the U.S. with a law that makes it illegal for private employers to require vaccines as a condition for employment. That new requirement appears to clash with parts of the mandate, which tells all private businesses with 100 or more employees to require them to get vaccinated against COVID-19 or get tested weekly for the respiratory virus.

The Montana law was passed earlier this year by the Republican-dominated state Legislature despite pushback from the state’s hospital association and other medical groups straining under the weight of a new surge in COVID-19 infections.

A Montana Hospital Association spokesperson said in an email on Thursday that their legal counsel will evaluate the new mandate to determine how to comply with federal and state law.

Another governor, Mississippi Republican Tate Reeves, also criticized Biden’s mandate announcement.

“The President has no authority to require that Americans inject themselves because of their employment at a private business,” Reeves wrote on Twitter. “The vaccine itself is life-saving, but this unconstitutional move is terrifying. This is still America, and we still believe in freedom from tyrants.”