Lord Cameron is among a number of former British politicians who were educated privately at Eton College in Berkshire.
After a majority voted to leave the EU, Lord Cameron resigned as prime minister.
Speaking in 2016, after leaving office, he defended his decision to call the referendum.
“I believe and still believe that the fact that we hadn’t had a referendum on this issue for 40 years, despite the fact that the European Union was changing … was actually beginning to poison British politics – it was certainly poisoning politics in my own party.
“And I think, more broadly, people felt ‘well, we have been promised referendums and they haven’t been delivered’ and people were beginning to feel very frustrated about this issue.”