The Unite union said no media outlets should give platforms for openly racist groups such as the KKK.

Jackie Pollock, Unite’s Industrial Officer said: “We are disappointed that Good Morning Ulster interviewed a member of the Ku Klux Klan – an organisation that has no democratic mandate which promotes a destructive and reactionary ideology.

“The BBC is the publicly funded, national broadcaster and has an overriding responsibility to wider society. We contrast Good Morning Ulster’s interview of a Ku Klux Klan representative with the recent failure of the corporation to provide any significant coverage of a huge anti-austerity march in the middle of London which involved 50,000 people.”

The flag of the KKK which was erected in Island Street at the start of the week was taken down after local discussions in the east of the city.

The BBC said: “BBC NI chose to interview a representative of the Ku Klux Klan following the appearance of a flag in East Belfast yesterday, a story which was reported in many media outlets in Northern Ireland. The representative was asked about any links or support in NI for his organisation. He was also challenged on his views. We also interviewed an American academic immediately after the interview to provide context about the nature of the KKK organisation.”

Northern Ireland first minister, Peter Robinson, described the flag as “grossly offensive”. The Democratic Unionist party leader said putting it up was an “intimidatory act”.

The MP for the area, Naomi Long, made a formal complaint on Tuesday about the presence of the KKK banner.

The flag controversy comes at a time when racist attacks and incidents are on the rise across Northern Ireland.

The annual benchmark report on human rights and racial equality by the Northern Ireland Council for Ethnic Minorities, released last month, said there were 982 racist incidents in 2013-14 compared with 750 such incidents during the previous year.

It noted that over the last five years 75% of all complaints to the Equality Commission in Northern Ireland about harassment in offices, shops or factories are related to racial abuse and intimidation.

Over the last year Northern Ireland has become one of the worst hotspots for racist crimes and race hate-linked incidents in the UK, but the authors of the report say the region is home to only 1% of all the non-EU/EEA migrants who have come into the UK