The controversial Illegal Migration Bill is set to become law as it has passed through the final stages in the House of Lords this week.
The bill will now go for royal assent and become law. It will mean that the home secretary has a legal duty to detain and remove anyone entering the UK illegally which has huge implications for children and young people.
Barnardo's CEO, Lynn Perry MBE, said: "Having warned of its serious implications for the safety and protection of children, we are deeply concerned that the Illegal Migration Bill is now set to become law.
"Not only will this Act make it legal to detain children for more than 24 hours, it will deny children the chance to put forward their case for asylum in the UK. It will also prevent some children who have been identified as victims of trafficking from receiving protection and support, including those who have suffered trauma and exploitation.
"We urge the Government to develop a strategic plan that protects and welcomes all displaced children who have fled their homes to seek refuge in the UK."