As the Delta variant fuels a new coronavirus wave, particularly in areas with underwhelming vaccination rates, Tennessee on Tuesday became the latest state where a governor has undermined efforts by local school districts to require students to wear masks as the new school year approaches.

Gov. Bill Lee, a Republican, signed an executive order on Tuesday essentially gutting any school district’s effort to require its students to wear masks.

According to the order, a student’s parent or guardian “shall have the right to opt out of any order or requirement” that the student “wear a face covering” at school, on school buses, or at school functions.

The number of new coronavirus cases in Tennessee has been steadily rising since July, according to a New York Times database. As of Sunday, Tennessee recorded its highest weekly average of coronavirus cases since late January.

Mr. Lee’s executive order comes days after video surfaced last week showing anti-mask protesters threatening doctors who expressed support for requiring face coverings during a local school board meeting in Williamson County.

Tennessee is one of several battlegrounds with a Republican governor who opposes mask mandates and local school officials who want them.

About two weeks ago, Gov. Ron DeSantis of Florida, a Republican and an ardent opponent of public health mandates, signed an executive order directing state officials to ensure that parents have the final say on whether their children wear masks in school this fall. On Sunday, the chairwoman of the Broward County School Board said the district had no choice but to defy Mr. DeSantis’s ban. “We’re living out the nightmare of the Covid pandemic, where so many people in our county, including members of our staff and others, are being impacted,” said Rosalind Osgood, on the CBS program “Face the Nation.” “We believe that we have a constitutional obligation to protect the lives of our students and staff.”

Last week, Mr. DeSantis and Gov. Greg Abbott of Texas both blocked local school districts from requiring masks or taking other measures to protect students from the coronavirus in the coming school year.

But several school districts have taken their fight to the courts.

The Texas Supreme Court on Sunday ruled that the state’s governor can ban mask mandates, at least temporarily. Some districts, though, vowed to maintain the requirements. On Tuesday, a judge in Bexar County ruled in favor of officials in the county and the city of San Antonio who had already put in place a mask requirement at schools, as well as county and city facilities, according to a reporter at KENS5 and a spokesman for the county.

This story was first reported in the New York Times