Washington: Hillary Clinton delivered a withering assault Tuesday on White House rival Donald Trump, painting the brash billionaire as a "dangerous" and manipulative businessman who would sink the US economy and cost Americans millions of jobs.

The Democratic flagbearer''s most direct and punishing condemnation of Trump''s business dealings yet came as the presumptive Republican nominee revealed unprecedented financial deficits heading into his general election push, the latest of several setbacks and self-inflicted wounds that have plunged his campaign into disarray.

Clinton piled on in her speech in Ohio, an important swing state where she argued that Trump''s lack of a plan to bring back manufacturing and other jobs could yank the nation back into recession.

"We cannot put a person like this, with all his empty promises, in a position of power over our lives," Clinton said in Columbus.

"We can''t let him bankrupt America like we are one of his failed casinos. We can''t let him roll the dice with our children''s futures," she thundered.

By laying into Trump''s corporate empire, Clinton aimed to disarm her rival''s potent claim that he can translate his business acumen into Oval Office success.

"He''s written a lot of books about business. They all seem to end at chapter 11," she quipped, referring to the US legal code that addresses bankruptcy and reorganization.

She claimed Trump had refused to pay workers their due and had his own products manufactured overseas -- moves she argued punished hard-working Americans.

"In America, we don''t begrudge people being successful, but we know they shouldn''t do it by destroying other people''s dreams," she said.

Despite his long track record as a businessman, "it turns out he''s dangerous there, too," Clinton said.

"Just like he shouldn''t have his finger on the button," she added, referring to the US nuclear arsenal, "he shouldn''t have his hands on our economy."

"Donald Trump''s ideas about the economy and the world will cause millions of Americans to lose their jobs."

- Seeking a reboot -

Trump shot back as Clinton spoke, arguing that she "surged the trade deficit with China 40 percent as secretary of state, costing Americans millions of jobs."

He announced he would deliver a speech Wednesday addressing "the failed policies and bad judgment of Crooked Hillary Clinton."

But the latest news cycle unquestionably has been unkind to the real estate tycoon.

He fired campaign manager Corey Lewandowski on Monday, seeking a reboot as he prepares to battle with Clinton whose campaign is well ahead of Trump''s in terms of finances and organization.

He has been hammered for making controversial statements after the Orlando massacre, including about Muslims, and for saying it would have been a "beautiful sight" if more people at the Florida club were armed in order to shoot back at the attacker.

His numbers have slid in several polls, and Republican leaders have continued to express ambivalence about their presumptive nominee.

- A ''different'' campaign -

The latest clash comes amid revelations that Trump''s campaign war chest lags woefully behind Clinton''s.

Trump has just $1.3 million in cash on hand, according to reports filed Monday with the Federal Election Commission.

Clinton''s campaign by contrast had more than $42 million in the bank as of May 31, its report showed.

Trump insisted he himself could line his campaign pockets with "unlimited" funds.

"If need be, there could be unlimited ''cash on hand'' as I would put up my own money, as I have already done through the primaries, spending over $50 million," he said in a statement.

He also insisted his campaign was prepared to embrace a new tone as it geared for battle with the Clinton machine.

"I think it''s time now for a different kind of a campaign" than the one that helped win the primary race, Trump told Fox late Monday as he justified Lewandowski''s departure.

Trump also brushed off the difficulty he has had in earning Republican leadership support, telling NBC he might not even need their blessing.

"I may be better winning it the opposite way than the more traditional way," he said.

But a revolt of sorts appeared to be brewing at next month''s Republican National Convention.

As many as 400 of the party''s 2,472 delegates who formally elect the Republican nominee have expressed support for a movement to stop Trump, according to the Washington Post.

The movement''s organizers aimed to draw bound delegates -- who must vote in line with primary results -- to the cause by insisting they be allowed to vote their conscience at the July convention, according to the paper.

AFP