A federal appeals court unanimously ruled against President Donald Trump on Thursday, refusing to reinstate his travel ban affecting people from seven Muslim-majority countries.

The ruling, issued by a three-judge panel on the San Francisco-based 9th Circuit Court of Appeals, means that refugees and citizens of the countries in question can continue entering the US — striking a blow to Trump’s ability to deliver on one of his key campaign promises.

“We hold that the Government has not shown a likelihood of success on the merits of its appeal, nor has it shown that failure to enter a stay would cause irreparable injury, and we therefore deny its emergency motion for a stay,” the panel said in its ruling.

Shortly after the ruling was announced, Trump posted a defiant message to Twitter:

“SEE YOU IN COURT,” Trump tweeted, foreshadowing a legal challenge that could play out in the Supreme Court.

The Justice Department said it is reviewing the court’s decision.