United States President Barack Obama just put a roadblock in Donald Trump's Muslim registry plans. 

The news comes just as Trump appears to have doubled down on his promise to create the registry in the wake of an attack claimed by ISIS in Berlin.

On Thursday, Obama formally dismantled a program that had once been used to register immigrants from more than 20 countries, placing a roadblock in the way of creating a Muslim registry.

The program – National Security Entry-Exit Registration Systems (NSEER) –has not been active since 2011, and it primarily targeted Muslim majority countries, mainly in the Arab world. 

Instituted after the Sept. 11, 2001 attacks on New York, the program required male immigrants from the 20 plus countries to register upon arrival in the US. They also had to regularly check-in with authorities during their time in the country.

Many saw the NSEERs program as a likely and easy avenue for President-elect Donald Trump to implement his promised Muslim registry. Members of Trump's transition team have also suggested that the program would again be made active once he took office. 

Activists and rights groups have also expressed fear that the program would not only be restarted but would be further expanded under Trump's administration.

Now, after Obama's action, Trump will have to start from scratch if he moves forward with create a registry for Muslim immigrants.

Following the attack, Trump was asked by reporters about his Muslim ban. He responded by saying: "You know my plans." Trump also insisted he has always been "100 percent correct" about what is happening, apparently referring to terrorism.

After his comments, Trump's former campaign manger, Kellyanne Conway, explained that any registry would be "more strictly tied to countries where we know they have a history of terrorism" and that it would not be a "complete ban."

Regardless, talk of a Muslim registry has led many to draw parallels to Germany of the 1930s when the Nazis rose to power and created a Jewish registry leading up to the Holocaust.