New Delhi, April 2 (IANS): A few Congress workers on Thursday protested union Minister Giriraj Singh's remark on party president Sonia Gandhi's skin colour that have triggered a row.

The workers protested outside Vithal Bhai Patel House in New Delhi area around 9.30 a.m. and were detained by police.

"Around 30-32 people were protesting and they have been detained. This is the only protest staged by the Congress, but we are ready to handle the situation if there are any other protests," Joint Commissioner of Police M.K. Meena told IANS.

The workers held posters and shouted slogans against Singh.

Some of them demanded Prime Minister Narendra Modi to act on the matter.

Giriraj Singh told reporters in Patna on Tuesday that he wondered if former prime minister Rajiv Gandhi had married a woman who was not white-skinned, would the Congress have accepted her as its president.

"If Rajiv Gandhi had married a Nigerian and if she wasn't white-skinned, would the Congress have accepted her as a leader," he said.

After the remarks caused outrage, he expressed regret and said his remarks were made during an off-the-record conversation.