Donald Trump 'wrong' president: Michelle Obama urges US to vote for Biden

Michelle Obama has ripped through Donald Trump at the opening of the Democratic National Convention, saying he is the "wrong president for our country" and urged Americans to vote for his challenger Joe Biden "like our lives depend on it."

In an emotional recorded message to the convention, the former US first lady said last four years had been difficult to explain to America's children.

"They see our leaders labelling fellow citizens enemies of the state, while emboldening torch-bearing white supremacists," she said.

The four-day Democratic National Convention (DNC) was initially scheduled to be held in Wisconsin but it began virtually on Monday amid the raging Covid-19 pandemic.

Former vice president Biden, 77, is challenging 74-year-old Trump, a Republican in the November 3 presidential election.

Senator Kamala Harris, 55, is all set to be formally nominated by the DNC as the first-ever Black as well as the first-ever American of Indian and African descent as a vice presidential candidate by a major political party.

Launching a blistering attack on Trump, Obama said children are torn from their families and thrown into cages and pepper spray and rubber bullets are used on peaceful protests for a photo op.

"Let me be as honest and clear as I possibly can. Donald Trump is the wrong president for our country. He has had more than enough time to prove that he can do the job, but he is clearly in over his head.

"He cannot meet this moment. He simply cannot be who we need him to be for us. It is what it is," 56-year-old Obama said in a poignant political speech.

Taking a swipe at Trump's presidency, she urged those who did not come out to vote in 2016 to make their vote count this time.

Obama said the country has been "living with the consequences" since the 2016 election results.

She said her message is likely to be unheard by some people as "we live in a nation that is deeply divided, and I am a Black woman speaking at the Democratic convention".

Obama cautioned that if Americans think things cannot possibly get worse, "trust me, they can; and they will if we don't make a change in this election. If we have any hope of ending this chaos, we have got to vote for Joe Biden like our lives depend on it".

Former US vice president and presumptive Democratic presidential candidate Biden, 77, will challenge 74-year-old Republican incumbent President Trump in the November 3 election.

Obama said the job of the president is hard and it "requires clear-headed judgment, mastery of complex and competing issues, devotion to facts and history, a moral compass, and an ability to listen and an abiding belief that each of the 330,000,000 lives in this country has meaning and worth".

"A president's words have the power to move markets. They can start wars or broker peace. They can summon our better angels or awaken our worst instincts. You simply cannot fake your way through this job," the former first lady said.

Obama lamented that in the presidential elections four years ago, too many people chose to believe that their votes didn't matter or may be because they were fed up.

"Whatever the reason, in the end, those choices sent someone to the Oval Office who lost the national popular vote by nearly 3,000,000 votes, she said adding that we've all been living with the consequences.

She said in the four years that her husband, former president Barack Obama, and vice president Biden left office, the state of America is very different.

More than 150,000 people have died, and our economy is in shambles because of a virus that this president downplayed for too long. It has left millions of people jobless. Too many have lost their health care; too many are struggling to take care of basic necessities like food and rent; too many communities have been left in the lurch to grapple with whether and how to open our schools safely.

"Internationally, we've turned our back, not just on agreements forged by my husband, but on alliances championed by presidents like (Ronald) Reagan and (Dwight) Eisenhower, Obama said.

Refering to the recent spate of killings of people from the African-American community, she said even as George Floyd, Breonna Taylor and a never-ending list of innocent people of colour continue to be murdered, "the simple fact that a Black life matters is still met with derision from the nation's highest office".

"Whenever we look to this White House for some leadership or consolation or any semblance of steadiness, what we get instead is chaos, division, and a total and utter lack of empathy," she said.

"Right now, kids in this country are seeing what happens when we stop requiring empathy of one another. They're looking around wondering if we've been lying to them this whole time about who we are and what we truly value," the former first lady said.

Meanwhile, President Trump on Tuesday hit back at Michelle Obama, describing her speech at the Democratic National Convention as "extremely divisive" and claimed that her husband Barack Obama's Oval Office performance is what put him into the "beautiful White House".

"She was over her head, and frankly she should've made the speech live, which she didn't do," Trump told reporters at a White House event held to commemorate the 100th anniversary of women's suffrage.

"I thought it was a very divisive speech. Extremely divisive," Trump said.