(CNN) Donald Trump on Wednesday refused to back off his claim that Humayun Khan, a Muslim-American US Army captain who was killed in the Iraq War in 2004, would still be alive had he been president at the time.

"Had I been president, Captain Khan would be alive today. We wouldn't have been in this horrible, horrible mistake, the war in Iraq," Trump said in an interview Wednesday with ABC News , in which he again falsely insisted that he was "opposed to the war in Iraq right from the beginning."

Khizr Khan, the father of the deceased US Army officer, called Trump's remark about his dead son "cruel" in a separate ABC News interview.

Trump's remarks come nearly three months after the real estate mogul first escalated a feud with the parents of the slain US Army officer after they criticized him at the Democratic National Convention. Trump suggested Khan's mother had not been "allowed" to speak and said the parents had "no right" to criticize him.

Trump's decision to repeat the statement flies in the face of his public statements of support for the Iraq War before and immediately after it started.

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