A day after President Trump sought to bar foreign nationals from entering the country to study at Harvard University, the college asked the courts Thursday to step in and stop him from using the force of the federal government to “pursue a government vendetta against Harvard.”

Harvard filed an amended complaint to a pending lawsuit in federal court amid an ongoing struggle between the nation’s president and the elite college.

“With the stroke of a pen, the DHS Secretary and the president have sought to erase a quarter of Harvard’s student body, international students who contribute significantly to the University and its mission and the country,” Harvard’s lawyers wrote in the new court filing. “Without its international students, Harvard is not Harvard.”

On Wednesday night, Trump invoked national security powers to impose a six-month block on student visa holders from entering the country to study at Harvard. He also said Secretary of State Marco Rubio would review the status of current international students case by case to determine whether their visas should be revoked.

“Our adversaries, including the People’s Republic of China, try to take advantage of American higher education by exploiting the student visa program for improper purposes and by using visiting students to collect information at elite universities in the United States,” Trump wrote Wednesday, referring to allegations the Chinese government poaches scientific advancements from American universities.

Trump’s actions were the latest escalation in the administration’s ongoing battle with elite universities, which he’s accused of fomenting anti-American ideology and failing to address instances of antisemitism. The Republican president’s push against the colleges has intersected with his efforts to limit immigration and ramp up deportations.

In particular, Trump has trained his ire on Harvard, which has resisted his demands and filed lawsuits against some of his actions.

Last month, Trump dramatically ramped up his assault on the college when his administration moved to prevent it from enrolling foreign students. Those there already, he said, must transfer. Harvard sued, and won a court order providing some temporary protections. That led the administration to change tactics with Wednesday night’s filing, now on national-security grounds.

Harvard’s response Thursday in federal court was an amended version of that previous suit. In the new filing, Harvard’s lawyers wrote neither approach has any basis in the law.

They said the president’s actions against the college constitute “a concerted and escalating campaign of retaliation by the government in clear retribution for Harvard’s exercising its First Amendment rights to reject the government’s demands to control Harvard’s governance, curriculum, and the ‘ideology’ of its faculty and students.”

Governor Maura Healey, who graduated from Harvard, said in a statement that Trump is “punishing our students and hurting the American economy, all as part of his agenda to silence anyone who disagrees with him. And he won’t stop at Harvard.”

Shelley Murphy and Matt Stout of the Globe staff contributed to this report.

Sean Cotter can be reached at sean.cotter@globe.com. Follow him @cotterreporter. Brooke Hauser can be reached at brooke.hauser@globe.com. Follow her @brookehauser.