Swamy said the nation "must reject the ridiculous" claim of Singh that the records show that the police official had spoken to him about the "harassment" allegedly meted out to him by Hindutva forces.
"The nation has not been provided with any evidence so far of what conversation, if any, took place or the duration of the call," he said.
"The photocopy of the telephone records that Singh produced before television cameras needs to be scrutinised since the number on which a call was made from Singh's telephone was to a general special investigation team number in Mumbai and not to any of the two numbers on which Karkare could be accessed," Swamy said.
Under attack over his claim about a call from Karkare, Singh on Tuesday produced phone records of the conversation the slain ATS chief had with him on 26/11 and sought an apology from Maharashtra Home Minister R R Patil and all others who had dubbed him a "liar".