An MP who shouted "apologise" at Zac Goldsmith after he delivered his runner-up speech at the Mayoral elections at City Hall said "it just came out".
Brent Central MP Dawn Butler told getwestlondon it "was a spontaneous moment after a short, meaningless speech" in the chamber, and said he should have mentioned his "horrible" Mayoral campaign.
The Conservative candidate was first placed under scrutiny after leaflets targeting different ethnic minorities were sent out which pledged to keep the "gold they keep at home" safe .
However, criticism stepped up after the Tory campaign raised links between Sadiq Khan and terrorists, which he said "was his job to flag up" in order to keep the city safe.
"If he had an ounce of apology, it would be different, but he didn't" said the Labour MP.
"Zac and the Prime Minister should be ashamed, if this happened to someone else with any other religion, they would be held to account."
Ms Butler, who has been a Member of Parliament since 2005, added she never expected such a campaign to be run by Mr Goldsmith.
"At the beginning, if you'd said Zac's running the nastiest campaign, I would've said 'shut up'," she said.
"Now, if I see him, I'll tell him to his face that he needs to publicly apologise and I will be holding them to account."
In a previous interview with getwestlondon , Mr Goldsmith said "he had run a positive campaign"
Sadiq Khan won the Mayoral election , which was announced the early hours of Saturday morning, with a historical landslide victory of 1,310,143 votes to become the first Muslim mayor of a major western capital.
In his first ever speech after being announced winner, he said the election campaigns had "not been without controversy".
Ms Butler, who has claimed to have experienced racism in Parliament in the past , said the city voted for someone who has "grit and determination".
On the result, she said: "No one can divide our community, I just look around and think this result, it's London.
"There will be a buzz around London, everyone will be proud of what we've done and what the party has achieved."
Zac Goldsmith has been approached for further comment.