The watchdog for equality and diversity in the UK has approached Reform UK after receiving complaints “alleging unlawful activity” following the airing of an ITV documentary that showed members using racist language.

The Equality and Human Rights Commission (EHRC) has said it has written to the political party , asking it to provide information “including what action the party is taking to comply with the Equality Act”.

ITV’s Undercover: A Year in Reform showed Black children being referred to as “animals”, while in another excerpt, a Reform activist said that asylum seekers should be put in concentration camps.

In another clip, a Reform member said that his area had become “infested” with Asian families.

A spokesperson for the EHRC said: “We have written to Reform UK regarding concerns expressed following ITV News’ investigation, Undercover: A Year In Reform, which aired last month. We have asked for more information including what action the party is taking to comply with the Equality Act 2010.

“Following the broadcast of ITV’s documentary, we received complaints alleging unlawful activity under the Equality Act 2010, including concerns about racial and sexual remarks expressed by councillors, prospective councillors and members. As with every complaint we receive, we will assess the information provided carefully and, following that consideration, take action where appropriate.”

The EHRC said that political parties must comply with the Equality Act, and “take steps to avoid discrimination or harassment including on the grounds of race, religion or belief and sex”.

The spokesperson added: “As Britain’s equality regulator and a national human rights institution, we recognise the right to freedom of expression is fundamental to our democracy and must be protected, even when dealing with complex and sensitive issues. Similarly, everyone has a right not to be discriminated against, including on the grounds of race, religion, belief or sex.

“The right to freedom of expression and the right to be free from discrimination are not mutually exclusive and must be considered together. We urge those in positions of authority to balance these rights appropriately and respectfully.”

Speaking at a press conference in central London on Monday evening, Mr Farage was asked about the EHRC’s letter to his party.

He told reporters: “We are entirely confident that our employment procedures and our vetting procedures are as rigorous as any other party in this country.

“What you can’t legislate against, what you can’t vet against, is people saying stupid things in certain circumstances.”

The party has previously insisted there is “no room for racism” in its ranks, and suggested the people involved in the documentary had either been suspended or left the party.

A Reform UK spokesman: "We are confident we have fully complied with our obligations under the Equality Act. There is no room for racism in Reform UK."