Speaking yesterday at the Recruitment and Employment Confederation (REC) in London, May claimed labour exploitation is "more common than we know" and called on all businesses to take action to eliminate it.
She was addressing a board meeting of the Gangmasters' Licensing Authority (GLA) about her department's work to crack down on labour exploitation.
At the meeting, she announced a number of measures the Government is taking to tackle this problem. These included the introduction of the Modern Slavery Bill later this month and a taskforce headed up by an anti-slavery commissioner to be named at a later date.
May said the Government is sending the "strongest possible message" that the UK "will not tolerate modern slavery".
"We will pursue these criminals and prevent them from operating and expand the operation to the source countries where these monsters exist," May said. "We will also lobby relevant Governments to change laws and policies."
Earlier this week, 300 police officers carried out raids linked to suspected exploitation of migrant workers in Kings Lynn in Norfolk, and March and Wisbech in Cambridgeshire. Police arrested nine people and closed down two recruitment agencies.
Retailer Supply Protocol
The Home Secretary praised many of the country's major retailers in signing up to the Retailer Supply Protocol, outlined in March this year. The protocol sets out how the GLA will work with suppliers, retailers and other organisations to prevent the exploitation and abuse of workers.
The aim is to make sure GLA licensing standards are applied throughout the supply chain to reduce worker exploitation.
After the meeting, REC chief executive Kevin Green said he strongly supports May's plans for an anti-modern day slavery bill.
"It's important that regulators, employers and recruiters work collaboratively to create greater transparency and accountability within supply chains," Green said.
"The REC and our members recognise the key role that our industry plays in ensuring safe recruitment practices are maintained. We will soon be issuing guidance to our members to help them identify and report issues of exploitation so this criminal activity can be eradicated once and for all."
