Washington (CNN) President Donald Trump signed a new executive order Tuesday to keep open the detention facility at Guantánamo Bay, Cuba, and opened the door to sending new prisoners there.

The decision is a major reversal of his predecessor President Barack Obama's policy.

During his Tuesday night State of the Union speech, Trump said he had just signed the order directing Secretary of Defense James Mattis to "re-examine our military detention policy and to keep open the detention facilities at Guantánamo Bay."

In his speech and order Trump raised the prospect of additional ISIS prisoners being sent to Guantánamo Bay.

"I am asking Congress to ensure that in the fight against ISIS and al Qaeda we continue to have all necessary power to detain terrorists wherever we chase them down, wherever we find them. And In many cases for them it will now be Guantánamo bay," Trump said.

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