Former Obama adviser Susan Rice said there is "no evidence" that implementing President Trump's travel ban would "make... the United States safer."

Rice made the comments on "This Week," one day after at least two terror attacks rocked central London.

She told George Stephanopoulos that the lack of evidence is why so many federal judges have been "skeptical" of the executive order.

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"By stigmatizing and isolating Muslims... we alienate the very communities here in the United States whose cooperation we most need," she said.

Rice said defeating terrorism is a "long-term challenge."

Federal Judges Derrick Watson of Hawaii, Theodore Chuang of Maryland and others have blocked Trump's executive order restricting immigration from several countries.

Watch the clip above.

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