London (CNN) You know things are going badly when even the writing on the wall falls off.

British Prime Minister Theresa May's attempt to relaunch her faltering premiership was badly derailed Wednesday when a keynote speech was marred by an interruption from a prankster, a prolonged coughing fit and finally the disintegration of the stage set behind her.

An often excruciating address to members of her party was punctuated by coughs, splutters and brief interludes to sip water. May was left fighting to finish, barely audible, in front of a packed hall full of delegates at the Conservative Party Conference in Manchester.

May, who lost her overall governing majority in the last election, had hoped to relaunch her premiership with her keynote speech. But soon after beginning her address, she was accosted by comedian Lee Nelson, real name Simon Brodkin, who strolled up to the stage and handed her a P45 -- a form that UK employees are given when they leave a company, similar to a "pink slip" in the US.

Hi @BorisJohnson, I gave Theresa her P45 just like you asked. pic.twitter.com/gzW0UluDMv — Simon Brodkin (@simonbrodkin) October 4, 2017

Brodkin, who has performed similar stunts in the past, including throwing money over former FIFA President Sepp Blatter at a press conference in 2015, told reporters that he was put up to it by Foreign Secretary Boris Johnson, a former rival to May in her leadership bid. "Boris told me to do it," he was heard as saying -- presumably in jest.

Britain's Prime Minister Theresa May holds up a throat lozenge given to her by Britain's Chancellor Philip Hammond .

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