The joint letter signed by Tom Cotton, Ted Cruz, Marco Rubio, and John Cornyn was reportedly sent to the White House on Tuesday.
"We urge you to consider transferring the worst of these Islamic State [Daesh] fighters to the detention facility in Guantanamo Bay, where they will face justice", senators wrote in the letter.
The senators stressed that "it is imperative" that nearly 700 "battle-hardened terrorists in northeast Syria" captured by US coalition partners with the Syrian Democratic Forces (SDF) not be released.
"If given the opportunity, many of them will take up arms against our Syrian and Iraqi partners or attempt to infiltrate the United States and Europe to carry out terror attacks against civilian targets, like they have already done in France and Belgium", they warned.
Commenting on the issue, Washington Free Beacon noted that the letter was timed to the 10th anniversary of former President Barack Obama's executive order to close the military prison. Obama, however, failed to fulfil his pledge since the Congress refused to allocate funds for the facility’s closure.
Addressing the situation around the facility, Trump announced in 2018 that he had signed an order to keep Guantanamo open but no new prisoners have been transferred to it since then.
* Daesh (ISIL/ISIS/IS/Islamic State) is a terrorist organisation banned in Russia