Donald Trump's campaign has said that the Republican Presidential nominee believes President Barack Obama was born in the United States, a major reversal from a line of attack he launched five years ago.

'In 2011, Mr Trump was finally able to bring this ugly incident to its conclusion by successfully compelling President Obama to release his birth certificate. Mr Trump did a great service to the President and the country by bringing closure to the issue that Hillary Clinton and her team first raised,' Trump spokesman Jason Miller was quoted as saying by CNN.

'Inarguably, Donald J Trump is a closer. Having successfully obtained President Obamas birth certificate when others could not, Mr Trump believes that President Obama was born in the United States,' Miller's statement read.

Earlier in the day, Trump had again refused to say whether he believes Obama was born in the US, despite recent efforts by his top surrogates to downplay the 'birther' controversy.

'I'll answer that question at the right time. I just don't want to answer it yet,' Trump had told The Washington Post.

Trump had for long endorsed the fringe theory about Obama, that he was born in Kenya and might even be a secret Muslim, during the 2012 election cycle, and was its largest driving force.

The White House eventually released President Obama's long-form birth certificate in 2011 -- showing that he was, indeed, born in Honolulu in 1961.