Inspectors will focus on firms who are wrongly classifying construction workers as self-employed when they should be on the books.

Contractors trying to fiddle the Construction Industry Scheme (CIS) or paying less than the minimum wage will also be targeted.

Mike Eland, HMRC’s Director General of Enforcement and Compliance, said: “We aim to help contractors and employers understand their responsibilities and comply with their obligations but we will also catch and deal with those who deliberately break the law.

“This is only fair to those businesses who do play by the rules and want to compete on a level playing field.