Several Republican governors on Thursday vowed to take President Biden to court over newly announced measures requiring workers to get vaccinated against the coronavirus.Biden unveiled a six-step plan after weeks of surging COVID-19 cases and hospitalizations and delivered a speech from the White House in which he expressed exasperation with the roughly 25 percent of eligible Americans who have refused to get the coronavirus vaccine.The president, as part of his plan, said the Labor Department would issue an emergency rule to require all private employers with 100 or more workers to mandate vaccines or weekly testing. Biden also ordered federal employees to get vaccinated in the next 75 days, with limited religious and medical exemptions.The moves escalated Biden's battle with GOP governors who have staunchly opposed government intervention on the pandemic, such as masking or vaccination requirements. A number of those governors swiftly pledged legal challenges to Biden's new efforts.