The 'Me!' hitmaker took to Twitter to tell Trump to ''stop playing my song'' and to call on his fellow Americans to join him in ''voting this monster out'' in the November presidential election.
He fumed: ''Dear Trump Campaign, f**k you. You're not invited. Stop playing my song. No thanks, Brendon Urie, Panic! At The Disco & company.
''Dear Everyone Else, Donald Trump represents nothing we stand for. The highest hope we have is voting this monster out in November. Please do your part: headcount.org.''
Brendon's fury at Trump comes hot off the heels of Tom Petty's family sending a cease and desist letter to the president after he played 'I Won't Back Down' at a campaign rally.
The late singer's widow Dana, ex-wife Jane, and children Adria and Annakim issued a statement slamming the US leader for using the track to ''further a campaign that leaves too many Americans and common sense behind'' after it was used at a gathering in Tulsa, Oklahoma, over the weekend, and stressed that they didn't support the president, and the music legend didn't either.
They said in a statement: ''Tom Petty's song 'I Won't Back Down' was used at Donald Trump's campaign rally in Tulsa, OK.
''Trump was in no way authorised to use this song to further a campaign that leaves too many Americans and common sense behind.
''Both the late Tom Petty and his family firmly stand against racism and discrimination of any kind.
''Tom Petty would never want a song of his used for a campaign of hate. He liked to bring people together. Tom wrote this song for the underdog, for the common man and for EVERYONE.''
The family again stressed they hadn't been ''complicit'' in the song being played and revealed they had sent a legal notice to the president's campaign organisers ordering him not to use the music again in future.
The statement continued: ''We want to make it clear that we believe everyone is free to vote as they like, think as they like, but the Petty family doesn't stand for this.
''We believe in America and we believe in democracy. But Donald Trump is not representing the noble ideals of either.
''We would hate for fans that are marginalised by this administration to think we were complicit in this usage.
''Concurrently, we have issued an official cease and desist notice to the Trump campaign. Adria, Annakim, Dana and Jane Petty.''
Tom died from an accidental overdose in October 2017, aged 66.
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