Donald Trump celebrated the news that he had won enough delegates to clinch the Republican nomination by attacking Barack Obama.
Trump said the president had done a "horrible job" as president and "allowed many countries to totally take advantage of him and us".
Responding to Mr Obama's comments that the billionaire tycoon has "rattled" world leaders, he also criticised the outgoing president for "airing his difficulties", adding: "He shouldn't be airing what he's airing where he is right now and I think you're going to see it stop pretty soon".
"We're a divided country, we have tremendous difficulty, tremendous problems, and we're going to solve those problems and we're going to solve them fast," he said.
Donald Trump has reached the number of delegates needed to clinch the Republican nomination for president, according to an AP count.Read the full story ›
Donald Trump has "rattled" world leaders and they have good reason to feel that way, according to Barack Obama.Read the full story ›
Donald Trump has labelled Hillary Clinton "crooked" and says he cannot wait to face her in November's US presidential election.Read the full story ›
A Donald Trump rally was interrupted after protesters lobbed rocks and bottles at police.Read the full story ›
Former US Republican presidential candidate Rick Santorum endorsed Donald Trump on Tuesday.
The 2012 and 2016 presidential runner said he had been swayed by the billionaire's list of possible Supreme Court nominees.
Santorum dropped out of the presidential race in February and initially threw his support to Senator Marco Rubio.
Speaking to Fox News, he said: "The most important issue is preserving the Constitution of this country and a liberal Supreme Court will destroy it".
Last Wednesday, Trump unveiled a list of 11 judges he would consider, if elected, to replace the late Antonin Scalia on the Supreme Court.
Pro-EU group admits it is behind 15-foot high graffiti which echoes a famous anti-Soviet artwork painted on the Berlin wall.Read the full story ›
Republican presidential nominee said that he was offered a personal invite from Cameron - but Downing Street declined to confirm his claims.Read the full story ›
Donald Trump has claimed the missing EgyptAir passenger plane was "blown out of the sky".
"A plane got blown out of the sky," the presumptive Republican presidential nominee said at a rally in New Jersey.
"And if anything, if anybody thinks it wasn’t blown out of the sky, you are 100% wrong, folks. Ok? You're 100% wrong."
He made the claim while criticising his likely rival for the presidency, Hillary Clinton, for her apparent reluctance to use the term "radical Islamic terrorism".
Earlier, Clinton said Trump was "not qualified" to be president in a fierce attack on his credentials and past comments.