The judge said the travel ban -- third version of the policy -- 'plainly discriminates on the basis of nationality'.
The small state becomes the first to challenge the ban, which they say violates the US Constitution.
The US District Judge Derrick Watson blocked the core provision of the revised executive order two weeks ago arguing that it violated Establishment Clause of the Constitution by disfavouring Muslims.
The Supreme Court is currently not in session, but can take emergency cases.
Hours before President Donald Trump's new travel ban was set to go into effect, a federal judge in Hawaii blocked the ruling.