UPDATE 1-Biden says Republican governors are undermining COVID safety response

(Adds Biden quote, background, Arizona law suit)

By Nandita Bose

Sept 16 (Reuters) - U.S. President Joe Biden on Thursday directed his ire at the governors of Florida and Texas, accusing the Republican leaders of "doing everything they can to undermine the life-saving requirements" he proposed to counter the spread of COVID-19.

Some Republican governors, including Greg Abbott of Texas and Ron DeSantis of Florida, have vowed to fight the vaccine mandate for big companies that Biden rolled out last week https://www.reuters.com/world/us/biden-deliver-six-step-plan-covid-19-pandemic-2021-09-09 in the face of surging U.S. COVID-19 hospitalizations and deaths, mostly among the unvaccinated.

Mississippi Governor Tate Reeves earlier this week likened Biden's mandate to tyranny.

"I propose a requirement for COVID vaccines, and the governor of that state calls it a 'tyrannical-type move?'" said Biden, noting that the pandemic has killed over 660,000 people in the United States.

"This is the worst type of politics...and I refuse to give in to it," Biden said, adding that the policies rolled out by the White House are "what the science tells us to do."

Some Republican-led states and a sizable minority of Americans have defied vaccine recommendations from health officials, arguing that mandates infringe on their personal freedoms.

With just 63% of the eligible U.S. population having received at least one vaccine dose, the U.S. vaccination rate now lags most developed economies.

Biden's vaccine policy is expected to face a string of legal challenges from Republicans, including Arizona Attorney General Mark Brnovich, who became the first to file a lawsuit against it on Tuesday.

DeSantis has threatened fines for cities and counties that require employees get vaccinated against COVID-19, saying they violate Florida state law.

(Reporting by Nandita Bose; Writing by Tyler Clifford; Editing by Heather Timmons and Bill Berkrot)