Oscar-winning director Steve McQueen has thrown his support behind demands for planned anti-slavery laws to be toughened up and extra protections to be included to stop victims being turned into criminals.
MPs and peers have warned that the Government's draft Modern Slavery Bill, which includes measures that will see human traffickers given maximum life terms, does not go far enough and parts "need a rewrite" so the criminal offences are simplified to ensure there are more convictions.
Victims must also be put at the heart of the legislation, with provisions that shield them from prosecution for crimes they were forced to commit while enslaved, the Joint Committee on the Draft Modern Slavery Bill said.
McQueen, whose 12 Years A Slave won best picture at the Oscars, said Britain can be "justifiably proud" of its anti-slavery tradition that stretches back to campaigners such as William Wilberforce and the Quakers.
In a statement released by the committee, he added: "The authors of this report can honourably stand in that tradition. They have listened to the evidence and considered it with great care. Their recommendations are humane and principled.
"More than that they have grasped the complexity of contemporary trafficking and forced labour in the United Kingdom and have set forth clearly the fundamentals of what is necessary to tackle it effectively.
"I warmly commend this report and pay tribute to the members of the committee who have produced it. Their work has honoured Parliament and the country."
The committee said estimates about the scale of modern slavery, which includes sex trafficking as well as forced criminal activity and labour, vary widely but it is believed there are thousands of victims of sexual exploitation in the UK.
Victims include British schoolchildren groomed, abducted and forced to have sex and people who are trafficked and enslaved once they are here, it added.
The MPs and peers called for the creation of six offences - slavery of children and adults, child exploitation, exploitation, child trafficking, trafficking, and facilitating the commission of an offence of modern slavery - in the Bill.
They also pushed for l egislation on supply chains to ensure that firms can "no longer turn a blind eye to exploitation occurring in their names" and urged the Government to take the lead by " eradicating modern slavery from its own supply chains".