The protesters said they wanted to convince Ader to reject the bill and refer it to a constitutional review. The issue has thrust Budapest back into worldwide headlines, with critics at the very highest levels across the world claiming Orban continues to damage democracy.
However, last week the US embassy in Budapest issued a statement critical of the legislation, while accusing lawmakers who backed it of targeting the Soros-founded university.
Orban, an early supporter of U.S. President Donald Trump, has said repeatedly he expects an end to frequent U.S. criticism in earlier years of Orban's weakening of the democratic system of checks and balances, the rule of law and increased control over the media and the courts.
"His name is perhaps the strongest example of those who support anything that weakens nation states, they support everything that changes the traditional European lifestyle", Orban said in an interview on public radio Kossuth, as cited by Bloomberg. "The amendment does not violate the constitution's article ten on the freedom of learning and teaching".
In a statement, President Janos Ader said he didn't believe the new law, which passed through parliament in a matter of days, infringed on academic freedom.
For the Soros-founded Central European University, Hungary is demanding bilateral agreements with the United States and the state of NY, where the school is also accredited.
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Two lap later proper safety vehicle was out after Antonio Giovinazzi suffered his second heavy crash. Yeah, he really squeezed me, but it was good fun and I had the inside for the next corner".
Demonstrators hold a placard reading "Free country, free university!" as they protest against the efforts to close Central European University, as part of Prime Minister Viktor Orban's plan to transform Hungary into an "illiberal state" in Budapest, Hungary, Sunday, Apr. 9, 2017. Budapest has denied targeting CEU and said it merely wanted to create a level playing field for all foreign universities operating in Hungary. CEU says parts of the bill directly target it, and could force it to close. Other chants included "A free country, a free university", "Orban get out", "Viktator!" and "Europe, Europe".
This bill will effectively force CEU from Hungary - where it occupies prime real estate in the centre - as it requires foreign universities to have a campus both in the capital and their home countries.
Orban, who faces elections in 2018, is not expected to backtrack on the legislation as it constitutes a major plank of his political strategy defending national interests against what his government calls foreign meddling in Hungarian affairs. The U.S. and Germany have condemned the law and called on Hungary to reconsider.
A law expected to be passed in May would force nongovernmental organizations getting more than $24,500 a year from overseas to register with authorities. The CEU operates in Budapest but is the only worldwide college with no branch outside Hungary.
The university says the legislation "seeks to make it impossible for CEU to offer American-accredited master's and doctoral degrees, as it has done with the full agreement of Hungarian authorities for many years".