Prime Minister Mette Frederiksen later condemned the incident in a social media post.
Siddique and his parents were accosted by a man wearing a t-shirt bearing the words “Fuck Islam” as left the parliament at Christiansborg.
The man told Siddique, along with his mother and 82-year-old father to “go home”. The incident was recorded on a video published by tabloid newspaper BT.
“Aren’t you planning to go home soon? You can take your parents with you, or whatever it is. Your Arabic culture has no place in Denmark, you’re not welcome here,” the man shouts in the video.
Siddique was born in Copenhagen and does not have Arabic heritage. His parents are originally from Pakistan.
Frederiksen subsequently strongly condemned the incident in a Facebook post.
“(Siddique) was yesterday subjected to an unheard-of racist attack right outside Christiansborg. That’s bad enough in itself. But what’s worse is that elderly parents were also subjected to an entirely unfair and boorish confrontation,” the PM wrote.
“I’m so upset about it that I will this evening ask parliament to reject the episode in unity. A racist attack on a family is an attack on all minorities. It has no place in Denmark,” she continued.
“And an attack on a democratically elected politician is an attack on democracy itself. Neither does this have any place in Denmark. My thoughts today go especially to Sikandar’s parents,” she added.
Siddique, a former member of the Alternative party who now sits as an independent, but is political spokesperson with the recently formed Independent Green Party, expressed his thanks after several political colleagues from both sides of the ideological divide pronounced their support.
“A thousand thanks for all the warm messages after what happened yesterday. It means very much, both for my parents and for me. We are fine under the circumstances and the police are now on the case,” he wrote on Twitter on Wednesday.