UK prime minister is the latest high profile politician to condemn Trump's remarks.
Despite being the frontrunner Trump sees 12 percentage point drop in latest Reuters/Ipsos poll.
The Republican list for the US presidential nominations is getting long - so here are the runners and riders.
The Republican presidential candidate said he 'sincerely' apologises for using 'an old joke about Joe Biden during his time of grief".
Name recognition counts enormously in American politics, just ask Hillary and Jeb.
Kentucky senator spoke at length against proposed reforms to the Patriot Act
Cruz said Mitt Romney's comments on the working class, not his stance on immigration reform, cost him the 2012 presidential election.
Activists now sorry they held fireside chat with gay marriage foe.
The issue is considered of utmost importance to Latino voters.
The likely Democratic candidate saw drops in Colorado and Iowa.
Former Florida Governor Jeb Bush appears to have lost his edge according to a new poll.
Cruz's strategy is simple: talk about God and Reagan at every opportunity.
With three Republicans now declared for the 2016 presidential campaign,IBTimes UK looks at how the candidates stack up
Tea Party-favourite Ted Cruz is first Republican to announce candidacy.
55-year-old Harvard graduate who rose to prominence prosecuting police brutality to be formally announced on Saturday.