The business mogul played Young's anthem Rockin' In the Free World as he launched his presidential campaign in New York City earlier this month (Jun15), and Young subsequently released a statement complaining about the usage and distancing himself from Trump's campaign.

The Apprentice star's team hit back by declaring they were fully authorised to use the song, and Trump has now entered the war-of-words himself, criticising Young in a series of posts on Twitter.com.

The businessman shared an image showing himself and Young shaking hands alongside a stock purchase agreement signed by the rocker, adding, "A few months ago Neil Young came to my office looking for $$ (money) on an audio deal & called me last week to go to his concert. Wow!... For the non-believer, here is a photo of Neil Young in my office and his $$ request - total hypocrite...

"Neil Young's song, Rockin' In The Free World was just one of 10 songs used as background music. Didn't love it anyway..."