A U.S. judge on Wednesday is due to consider whether to order Republican President Donald Trump's administration to facilitate the return to the U.S. of Venezuelan migrants detained in El Salvador, potentially opening a new front in a major challenge to Trump's aggressive deportation policy.

A federal judge posed a new threat to President Donald Trump’s hardline immigration policies, telling government lawyers he may order the US to facilitate the return of alleged Venezuelan gang members who were deported to a notorious prison in El Salvador.

The ruling, which is limited to the Southern District of Texas, prohibited the administration from using the wartime law because the president’s claims about a Venezuelan gang do not add up to an “invasion.