President Donald Trump signed an executive order Thursday calling for the dismantling of the U.S. Education Department, advancing a campaign promise to take apart an agency that’s been a longtime target of conservatives. Trump has derided the Education Department as wasteful and polluted by liberal ideology. However, completing its dismantling is most likely impossible without an act of Congress, which created the department in 1979. Republicans said they will introduce a bill to achieve that. The department, however, is not set to close completely. The White House said the department will retain certain critical functions. Trump said his administration will close the department beyond its “core necessities," preserving its responsibilities for Title I funding for low-income schools, Pell grants and money for children with disabilities. The White House said earlier it would also continue to manage federal student loans. The president blamed the department for America’s lagging academic performance and said states will do a better job. “It’s doing us no good," he said at a White House ceremony. Already, Trump's Republican administration has been gutting the agency. Its workforce is being slashed in half, and there have been deep cuts to the Office for Civil Rights and the Institute of Education Sciences, which gathers data on the nation’s academic progress. Advocates for public schools said eliminating the department would leave children behind in an American education system that is fundamentally unequal.