article_snippet: David Cameron will not be able to continue as Tory leader until 2020, Iain Duncan Smith warned today as speculation over the Prime Minister's future mounted.
article_snippet: The remarks triggered the start of an unofficial Tory leadership race, after Tory also tipped Boris Johnson, George Osborne and Theresa May as potential successors.
article_snippet: But at the very least David Cameron would need to stand aside several months before May 2020 to give David Cameron successor time to prepare for the general election.
article_snippet: There has been speculation that David Cameron could quit after David Cameron promised 2017 referendum on leaving the EU, whatever the outcome.
article_snippet: Mr Duncan Smith, the Work and Pensions Secretary, told BBC1's Andrew Marr Show the PM would choose the timing of David Cameron departure and David Cameron would be 'sorry to see David Cameron go'.
article_snippet: David Cameron backed Boris Johnson, Theresa May and George Osborne as potential successors when David Cameron quits as Tory leader .
article_snippet: In the BBC interview when the Tory leader announced the Tory leader plans to stand down, Samantha Cameron made a rare appearance on screen to endorse Samantha Cameron husband as the right man to lead the country .
highlights_snippet: PM tipped Boris Johnson, George Osborne and Theresa May as leaders .