Washington - President Donald Trump will phase out a programme that has protected hundreds of thousands of young immigrants brought into the US illegally as children and call for Congress to find a legislative solution to protect the immigrants, sometimes known as "dreamers".That's according to two people who were briefed on the plan set to be announced later on Tuesday. They spoke on condition of anonymity to discuss the plans before the announcement.Trump suggested in an earlier tweet that it would be up to Congress to ultimately decide the fate of those covered by President Barack Obama's Deferred Action for Childhood Arrivals, or DACA programme, which has provided nearly 800 000 young immigrants a reprieve from deportation and the ability to work legally in the US.He tweeted: Congress, get ready to do your job - DACA!— Donald J. Trump (@realDonaldTrump) September 5, 2017 "Make no mistake, we are going to put the interest of AMERICAN CITIZENS FIRST!" Trump added in a second, retweeted message. "The forgotten men & women will no longer be forgotten."Trump has no announcement on his Tuesday schedule, but Attorney General Jeff Sessions, a harsh opponent of the programme, scheduled a press briefing on the topic later on Tuesday. It's the same day as a deadline set by a group of Republican state officials who said they would challenge DACA in court unless the Trump administration rescinded the programme.Many believe the programme would not hold up in court.Trump's expected plan to take a hard line on young immigrants unless Congress intervenes threatens to emphasise deep divisions among Republicans who have long struggled with the issue, with one conservative warning of a potential "civil war" within the party. Congressional Republicans have a long history of being unable to act on immigration because of those divisions.Republican Representative Ileana Ros-Lehtinen tweeted: After teasing #Dreamers for months with talk of his "great heart," @POTUS slams door on them. Some "heart"...— Ileana Ros-Lehtinen (@RosLehtinen) September 4, 2017 Trump's decision comes after a long and notably public deliberation. Despite campaigning as an immigration hard-liner, he has said he is sympathetic to the plight of the immigrants who came to the US illegally as children and in some cases have no memories of the countries they were born in.But his approach - essentially kicking the can down the road and letting Congress deal with it - is fraught with uncertainty and political perils that amount, according to one vocal opponent, to "Republican suicide."Still other Republicans say they are ready to take the issue on.The Obama administration created the DACA programme in 2012 as a stopgap as it pushed unsuccessfully for a broader immigration overhaul in Congress. Many Republicans say they opposed the programme on the grounds that it was executive overreach.