Mr Zardari, who is under criticism for visiting Britain while Pakistan is suffering from devastating floods, was in the middle of a speech when an elderly man in the 1,000 strong crowd hurled both shoes at him. The gesture is considered a traditional insult in Islam. An unidentified man was later ejected by police and security officials from the meeting, which was marked by noisy protests outside.
"Zardari was in the middle of a long campaign speech when a man towards the back of the crowd hurled the shoes at him," said one eyewitness. "They landed short of him, and it wasn't clear what exactly the man was protesting about.
In an interview with the Sunday Telegraph, Mr Zardari dismissed claims that he should have stayed at home, saying the trip had resulted in the floods receiving far more international attention than they might otherwise have done. He also said that his visit - which also included a meeting in Paris with President Nicholas Sarkozy - had been planned three months ago, in full knowledge that Pakistan's monsoon season was coming.
"These meetings are planned months in advance, and my coming abroad has drawn more attention to them than I myself would have been able to draw," he said.
He was joined in defence of his visit by his 21-year-old son, Bilawal Bhutto Zardari, who today opened a London donation point for victims of the floods, which have killed around 1,500 people and left millions more homeless and in need of aid.
"My father's doing all that he can to aid the people of Pakistan. His personal presence in Pakistan could not have done there what he did here," he said, speaking at the Pakistani High Commission in Knightsbridge. "This is not a time to play politics. We need to do what is necessary to help our brothers and sisters in Pakistan."
Mr Bhutto Zardari, whose mother Benazir was assassinated in Pakistan in 2007, added that his father had raised tens of millions of pounds for flood victims during his round trip to France, Britain and Abu Dhabi.
Critics had claimed that the real motivation for Mr Zardari to press ahead with the visit was so that he could attend this afternoon's political rally in Birmingham of his Pakistan People's Party, where he was expecting to court party funders. It had been speculated that his Oxford-educated son, who is the heir apparent to the party leadership, was going to make a maiden political speech at the meeting, but today he insisted that he had never planned to attend. He said he did not plan to enter politics until had he had completed further studies, "as I promised my mother".