WASHINGTON, Oct 12 (Reuters) - Boeing Co (BA.N) said on Tuesday it will require its 125,000 U.S. employees to be vaccinated by Dec. 8 under an executive order issued by President Joe Biden for federal contractors. "Boeing is requiring its U.S.-based employees to either show proof of vaccination or have an approved reasonable accommodation (based on a disability or sincerely held religious belief) by Dec. 8," the largest U.S. planemaker said. The Society of Professional Engineering Employees in Aerospace (SPEEA) union said it was "talking with employers to ensure implementation gives proper consideration to members concerns, health issues and abides by the provisions of our negotiated contracts." Just over 5,000 Boeing employees are in Texas, where Republican Governor Greg Abbott issued an executive order on Monday barring COVID-19 vaccine mandates by any entity, including private employers. read more"Due to the Texas EO, the Boeing vaccination requirement announced today does not apply to local sites immediately. However, once these sites become covered under the Biden EO, we expect that they will subject to the vaccination requirement," a Boeing spokeswoman said. Major U.S. airlines have said they will also meet the deadline imposed on federal contractors, including American Airlines (AAL.O), Southwest Airlines Co (LUV.N), JetBlue Airways Corp (JBLU.O) and Alaska Airlines (ALK.N), as has aircraft parts manufacturer Spirit AeroSystems (SPR.N). The White House announced the Dec. 8 deadline for employees of federal contractors last month and the requirements are expected to cover millions of employees. Government contractors International Business Machines Corp (IBM.N) and Raytheon Technologies Corp (RTX.N) have also said they will require all U.S. employees to be vaccinated. The White House is adding clauses to future government contracts mandating inoculations. Steve Cave, a King & Spalding attorney who specializes in government contracts, told Reuters last month he expects the order will affect tens of millions of U.S. workers or more. The Labor Department separately plans to issue an emergency temporary standard (ETS) requiring employers with more than 100 workers to have them inoculated or tested weekly - a policy expected to cover more than 80 million workers. But that has still not gone to the White House regulatory office for review, suggesting the ETS is still at least weeks away.