Hillary Clinton labeled her Republican rival Donald Trump “divisive and dangerous” and “unmoored” on Thursday, saying his recent behavior shows he's not qualified to be president.

The Democratic presidential front-runner unleashed her sharpest attacks yet on Trump, the presumptive GOP nominee, in an exclusive interview with CNN's Chris Cuomo in Park Ridge, Illinois.

She pointed to Trump’s attacks on British politicians, his willingness to speak with North Korean dictator Kim Jong Un, his call for the United States to back away from the North Atlantic Treaty Organization and his assertion that more countries should have nuclear weapons, and said it “adds up to a very troubling picture.”

“I know how hard this job is, and I know that we need steadiness as well as strength and smarts in it, and I have concluded he is not qualified to be president of the United States,” Clinton said.

When asked whether Trump was qualified in April, Clinton told CNN's Jake Tapper, “Well, the voters will have to decide. I’m going to lay out my qualifications to be president.”

On Thursday, Clinton was particularly critical of Trump’s proposal to ban Muslims from entering the United States, calling the idea “provocative” and saying it sends a “message of disrespect” to important majority-Muslim nations that are U.S. allies.

“When you run for president of the United States, the entire world is listening and watching,” she said. “So when you say you’re going to bar all Muslims, you're sending evidence to the Muslim world, and you’re also sending a message to terrorists. ... Donald Trump is essentially being used as a recruiter for more people to join the cause of terrorism.”

Trump later in the afternoon shot back in a statement, saying, “The fact that Hillary thinks the temporary Muslim ban, which she calls the “Muslim ban”, promotes terrorism, proves Bernie Sanders was correct when he said she is not qualified to be President.”

“Ask Hillary who blew up the plane last night – another terrible, but preventable tragedy,” the statement added. “She has bad judgment and is unfit to serve as president at this delicate and difficult time in our country’s history.”

Clinton said she’s not going to respond to Trump’s attacks on her as an “enabler” of her husband Bill Clinton’s marital infidelities and treatment of women. “I know that’s exactly what he’s fishing for, and I’m not going to be responding,” she said.

Instead, she said, she plans to focus her attacks on Trump on “what he says about other people” –a cue the pro-Clinton Priorities USA super PAC took in launching its first anti-Trump ads, highlighting insults he has hurled at women.

“I’m going after him exactly on those issues and statements that are divisive and dangerous, and I actually think that’s what the American people want to see,” Clinton said.

Clinton also addressed the disappearance of EgyptAir Flight 804, saying the disaster “shines a very bright light on the threat that we face from organised terror groups.”

“It reinforces the need for American leadership – the kind of hard, steady leadership that only America can provide,” Clinton said.

EgyptAir Flight 804 disappeared early Thursday morning with 66 people on board above the waters of the Mediterranean Sea and searches have found the plane’s wreckage. (CNN)

• Photo shows Donald Trump.

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