Former UN ambassador Nikki Haley has moved closer to the widely-expected launch of her US presidential campaign - previewing a "big announcement" that looks certain to confirm her as an early rival to frontrunner Donald Trump in the race for the Republican nomination. The move would make her just the second declared Republican candidate and could set the stage for a more combative phase of the campaign, potentially putting her in the sights of the former US president. Ms Haley's campaign sent an email to supporters yesterday inviting them to a 15 February event in Charleston. There she will declare...