Donald Trump prizes his willingness to fight back, and now the presumptive Republican nominee is sparring with leaders of a longtime U.S. ally: Great Britain. It comes as, on the Democratic side, some embarassing news for the campaign of Bernie Sanders, ahead of Tuesday's double primaries in Oregon and Kentucky. Josh Robin wraps up the latest from the campaign trail.
It's considered among the strongest of alliances: the generations-old bond between the United States and the United Kingdom.
Now, a dispute over values is unleashing a transatlantic row between Donald Trump, and both prime minister David Cameron and London's new mayor, Sadiq Khan.
At issue is Trump's proposal to bar Muslims from the United States.
"I think his remarks are divisive, stupid and wrong," said Prime Minister Cameron.
Trump has since said the plan was a suggestion, and anyway would make an exception for Khan, who is Muslim. On Monday, the new mayor seemed to say thanks but no thanks.
"Donald Trump and his advisers, your views on Islam are ignorant," Mayor Khan said.
"I think they're very rude statements," Trump told ITV. "And frankly, tell him I will remember those statements."
Trump's frostiness with the British leaders has Democrat Hillary Clinton pouncing. She says the presumptive Republican nominee seems friendlier with Russian president Vladimir Putin.
Clinton was in Kentucky, taking on a protester and hoping to halt rival Bernie Sanders from a Tuesday sweep. But it was Trump largely as her target, saying voters will see through him.
"They're going to be looking at that TV screen and saying, 'He still doesn't have anything to tell us?'" Clinton said.
Sanders was in Puerto Rico, which votes next month.
"All children, on this planet, in Puerto Rico, in the 50 states must be entitled to a good, quality public education," Sanders said.
Meanwhile, word emerged Monday that a Vermont college once run by his wife Jane is closing, saddled with financial problems from a real estate purchase she oversaw.