Hillary Clinton Releases Tax Return In Challenge To Donald Trump

US presidential candidate Hillary Clinton's campaign has released her tax return - and challenged Donald Trump to do likewise.

Mrs Clinton and her husband last year paid an effective federal tax rate of 34.2%, a combined federal, state and local effective rate of 43.2% and donated 9.8% of their income to charity, according to the campaign.

The Democratic White House hopeful's tax returns have been made public in some form every year since 1977.

Her running mate, US Senator Tim Kaine of Virginia, also released his tax return, showing he and his wife paid a federal effective tax rate of 20.3% in 2015, the campaign said.

US presidential candidates customarily release their filings, though there is no legal requirement to do so.

Clinton aide Jennifer Palmieri said in a statement the campaign continues "to set the standard for financial transparency".

"In stark contrast, Donald Trump is hiding behind fake excuses and backtracking on his previous promises to release his tax returns," she added.

Ahead of November's election, the Clinton camp is seeking to undermine the trustworthiness of her Republican rival, Mr Trump.

The New York businessman has refused to disclose any of his tax returns, saying they are no one's business and reveal little.

Mr Trump has cited an ongoing audit by the Internal Revenue Service, though the agency has said he is free to release his returns while under audit, as President Richard Nixon once did.

Mitt Romney, the 2012 Republican presidential candidate, and other conservatives have said Mr Trump's refusal raises questions about his finances.

Critics have suggested Mr Trump's filings could contradict his claims about his net worth and his charitable contributions.

Politico has reported that Mr Trump paid zero to very little taxes for two years in the 1990s.

Mrs Clinton released an online video on Friday of high-profile Republicans urging Mr Trump to release his taxes.

On Thursday, she raised the issue during an economic speech in Michigan.

"He refuses to do what every other presidential candidate in decades has done and release his tax returns," she told the crowd.

Meanwhile, Mr Trump insisted he was not serious when he said repeatedly this week that President Barack Obama was the founder of the Islamic State group.

The businessman said the media has misconstrued his words, tweeting: "THEY DON'T GET SARCASM?"