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Reuters
Barack Obama will accuse President Donald Trump of treating the White House like “one more reality show”, in a speech to the Democratic convention.
The former US president will say his Republican successor “hasn’t grown into the job because he can’t”.
In a White House news conference, Mr Trump hit back that he was only elected because Mr Obama did a “terrible job”.
On the third night of the Democratic conference, Kamala Harris will accept the vice-presidential nomination.
The Democratic presidential nominee, Joe Biden, will cap off the four-night convention with a speech on Thursday.
The Biden-Harris ticket will challenge President Trump and his Vice-President Mike Pence for the White House in the election on 3 November.
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What will Obama say?
On Wednesday night, Mr Obama will unleash possibly his most scathing attack yet about Mr Trump, speaking from the Museum of the American Revolution in Philadelphia.
According to pre-released excerpts of his remarks, he will say: “He’s [Mr Trump] shown no interest in putting in the work. No interest in finding common ground.
“No interest in using the awesome power of his office to help anyone but himself and his friends.
“No interest in treating the presidency as anything but one more reality show that he can use to get the attention he craves.”
He will say the consequences of the Trump presidency have been “our worst impulses unleashed, our proud reputation around the world badly diminished, and our democratic institutions threatened like never before”.
Mr Obama will then pivot to encouraging voters to elect his former vice-president, Mr Biden – praising him as “my friend” and “a brother” – in 76 days’ time.
Former US presidents mostly tend to observe a dignified public silence about their successors.
But Mr Obama warned four years ago while still in office that he would regard it as a “personal insult” if Americans elected Mr Trump, then the Republican candidate and a former star of TV’s The Apprentice.
The 44th president has become gradually more outspoken about his successor as he has watched him dismantle his legacy.
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Who else is speaking at the convention?
In a pre-recorded speech on Wednesday night, Hillary Clinton, the 2016 Democratic nominee, will also assail the man who thwarted her White House ambitions.
According to excerpts from her prepared remarks, she will say: “I wish Donald Trump had been a better president. But, sadly, he is who he is.”
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She will add: “For four years, people have said to me, ‘I didn’t realise how dangerous he was.’ ‘I wish I could go back and do it over.’ Or worst, ‘I should have voted.’
“Well, this can’t be another woulda coulda shoulda election.”
The former first lady and ex-secretary of state will urge Americans: “No matter what, vote. Vote like our lives and livelihoods are on the line, because they are.”