The 25-year-old said: "I've complained to the WBA and IBF [who] in the next 24 hours will tell me who he is.
"On tape you see him around Peterson's corner celebrating. It's bad for boxing we want fair fights and justice."
The WBA official who Khan alleges was interfered with has refused to tell the BBC who the man sat next to him was.
On Thursday Khan accused an unidentified man of "interfering" with officials and the judges' scorecards on his Twitter page by posting a number of images from last month's fight in Washington.
The Bolton fighter claimed the man talked to WBA supervisor Michael Welsh and interfered with the judges' scorecards.
However, when contacted by BBC Sport, Welsh refused to answer any questions about the mystery man or what was said.
"I want to know who this man is," Khan added on Sky Sports News.
"He had no accreditation. At the end of the fight he was straight over Peterson's people, celebrating with them.
"There were lots of amendments made on the scorecards, which I've never seen before. Why did it take so long to get the cards out?"
Khan's business manager, Asif Vali, said that they had written to the boxing authorities for explanations to several areas of concern.
"We did the table plan with Golden Boy Promotions and the WBA official was already in his seat and the IBF official was already in his seat, so who is this person?" he asked.
"What's he doing talking to the WBA? Why is he handling the slips?
"These are legitimate questions and if they give us sufficient reasons for it then I'll accept it. I want to see what the reasons are.
"We're not saying there is foul play involved in any way, shape or form. I just need the answers for the sequence of events that have taken place. Nothing else.
"I'm not accusing any of the bodies. Lamont Peterson is the champion and good luck to him for 2012."
My take is that Amir Khan is really stunned by the loss and he looking for excuses to try to explain it away. If there were people who thought there was wrongdoing or thought the scoring in the fight was off, they would have been screaming murder. That happens all the time with fights in the United States, regardless of the nationality of the fighters. There has been no such outcry here. Khan is really making himself look back. It's very flimsy what he's putting out to back up his claims
Khan's appeal against the controversial points decision to hometown fighter Peterson, which cost him his WBA and IBF light-welterweight titles, will be held later this month.
The president of the WBA, Gilberto Mendoza, has told BBC Sport that he is examining Khan's Twitter allegations and will make a response to Khan's camp within the next 24 hours.
The IBF told BBC Sport that "with regards to the IBF master scorecard we can assure that it has not been tampered with".
Among a string of tweets, Khan alleged that the unidentified man started to "interfere" with Welsh in round six and continued to do so until the end of the fight.
He also claims that the man talked to Welsh and handled the scorecards, which were handed to Welsh at the end of each round, and that Welsh admitted after the fight that his scorecards did not match the others.
Last month Khan had told of his unhappiness with the performance of referee Joe Cooper - who deducted Khan two points for pushing - and alleged scorecard irregularities.
Khan's trainer, Freddie Roach, told BBC Sport he believes his charge "got screwed".
Roach said he wanted to see Cooper suspended from officiating future world title fights and that "the fight should 100% be looked into".
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"I have no knowledge of any wrongdoing but it was unusual how long it took [for the scorecards to be tallied]," said Roach, Khan's trainer since 2008.
"Wrongdoing in boxing is always hard to prove but we got screwed in that fight. I hope something is done about it.
"I'd like to see the DC Boxing and Wrestling Commission look into the fight and I think the WBA and IBF - the sanctioning bodies - should be involved also."
Asked if his suspicions were aroused on the night, Roach said: "It goes through your mind [that there may be wrongdoing]. I mean, how hard can it be to add 12 rounds of boxing up?
"And Amir had two points deducted for pushing - the first time I've ever seen that."
Amir Khan claims he saw an unidentified man who "interfered" with officials during his defeat by Lamont Peterson celebrating with the winner.