President Trump has instructed the Department of Homeland Security to assist the Justice Department in constructing a legal case in defense of his temporary travel ban on nationals from seven Muslim-majority countries, CNN reported on Thursday.

Several Trump administration sources told the news network that some White House intelligence officials are concerned about the order and the potential politicization of intelligence.

“DHS and DOJ are working on an intelligence report that will demonstrate that the security threat for these seven countries is substantial and that these seven countries have all been exporters of terrorism into the United States,” one senior White House official told the news source.

“The situation has gotten more dangerous in recent years, and more broadly, the refugee program has been a major incubator for terrorism,” the official added.