The Prime Minister has been urged in the Lords to take a personal lead in tackling "Dickensian" conditions faced by millions of vulnerable children in England.
Labour's Baroness Dean of Thornton-le-Fylde said a report by the Children's Commissioner for England Anne Longfield had exposed "horrific" figures.
Opening a debate on the report, Lady Dean said it was a "sad indictment of our society today" that so many children were regarded as living vulnerable or high-risk lives.
She said the findings needed a response at prime ministerial level if the situation was to be tackled.
"Only by Mrs May expressing her determination that this scandal will now be solved, that Government departments will work together, is there any chance that progress will be made," Lady Dean said.
Former High Court judge and president of the family division, Baroness Butler-Sloss, warned that only the "tip of the iceberg" had been exposed over the trafficking of children.
She said trafficked Vietnamese children were being forced to work in cannabis farms: "They are being treated by the Crown Prosecution Service very often as offenders and not victims, despite being locked in and ill-treated."
Lady Butler-Sloss also warned about a "new form of modern slavery" where thousands of children were being picked up by gangs, taken from their homes and moved to other towns and cities, where they were used to peddle drugs.
She said these children were too often treated as offenders rather than victims. "They are controlled, abused and exploited," Lady Butler-Sloss told peers. "This is an emergency and more needs to be done."