Donald Trump vowed to unite the Republican party after his landslide victory in Indiana set the property mogul up to be its nominee and cleared the way for an intense fight against Hillary Clinton for the White House.

But Mr Trump also sent a warning shot across the bows of the party establishment after recent comments from several high-profile Republicans that they could never support the tycoon. “Honestly, there are some people I really don’t want. I don’t think it is necessary. People will be voting for me, they’re not voting for the party,” he told NBC.

Mrs Clinton, who is leading in national polls, appeared to relish the fight in prospect, pitching herself in a fundraising tweet as the “only one candidate left who can stop a Trump presidency”.