President Donald Trump faced criticism this week over claims he made about two separate phone calls: one with the leader of the Boy Scouts of America and another with the president of Mexico.

The president's seemingly untruthful statements join a list of his previous ungrounded claims, coming as he consistently reprimands the media for what he interprets as dishonesty in stories covering his administration

Trump is no stranger to pushing falsehoods or unsubstantiated claims. Here are some examples:

Obama birtherism theory

For years, Trump perpetuated the myth that President Obama was not born in the United States, often using tweets to push the claim, starting in 2011.

Made in America? @BarackObama called his 'birthplace' Hawaii "here in Asia." http://t.co/dQka2PIr — Donald J. Trump (@realDonaldTrump) November 18, 2011

Despite the president releasing his long-form birth certificate in 2011, Trump only conceded at a September 2016 news conference used to promote his new D.C. hotel that Obama was born in the United States.

“President Barack Obama was born in the United States, period,” Trump said. “Now we all want to get back to making America strong and great again.”

Born in Hawaii in 1961, Obama released his short-form birth certificate from the Hawaii Department of Health in 2008. He released his long-form birth certificate in 2011, saying he "believed the distraction over his birth certificate wasn’t good for the country."

But that didn't stop Trump from continuing to cast doubt, based on U.S. law that only a "natural born Citizen, or a Citizen of the United States, at the time of the Adoption of this Constitution, shall be eligible to the Office of President."

Let's take a closer look at that birth certificate. @BarackObama was described in 2003 as being "born in Kenya." http://t.co/vfqJesJL — Donald J. Trump (@realDonaldTrump) May 18, 2012

Always remember, I was the one who got Obama to release his birth certificate, or whatever that was! Hilary couldn't, McCain couldn't. — Donald J. Trump (@realDonaldTrump) June 29, 2014

Attention all hackers: You are hacking everything else so please hack Obama's college records (destroyed?) and check "place of birth" — Donald J. Trump (@realDonaldTrump) September 6, 2014

Claims of ‘serious voter fraud’ in 2016 election

Even after he won the election, Trump continued to insist that voter fraud occurred -- that he would have won the popular vote if not for "millions of people who voted illegally," but provided no evidence to support the claim.

In addition to winning the Electoral College in a landslide, I won the popular vote if you deduct the millions of people who voted illegally — Donald J. Trump (@realDonaldTrump) November 27, 2016

Clinton won the popular vote by nearly 3 million ballots.

In December, Vice President-elect Mike Pence, defended Trump, citing a Pew study as the source for the "millions" who allegedly voted illegally.

But the Pew study's primary author, David Becker, tweeted in response to references to his research: "As primary author of the report the Trump camp cited today, I can confirm the report made no findings re: voter fraud. We found millions of out of date registration records due to people moving or dying, but found no evidence that voter fraud resulted. Voter lists are much more accurate now than when we issued that study in 2012, thanks to the 20 states sharing data through @ericstates_info."

In another tweet, Trump named Virginia, New Hampshire and California as three states with "serious voter fraud." There is no evidence to back up the claim, and it's unclear why those states were singled out.

Serious voter fraud in Virginia, New Hampshire and California - so why isn't the media reporting on this? Serious bias - big problem! — Donald J. Trump (@realDonaldTrump) November 28, 2016

ABC News reached out to election officials in all 50 states shortly before Election Day and not one had any evidence or reason to believe that widespread voter fraud has or would occur in their states.

Obama founded ISIS

At an August rally in Florida, Trump told supporters that President Obama is the "founder of ISIS."

"ISIS is honoring President Obama," he said. "He is the founder of ISIS. He founded ISIS. And I would say the co-founder would be crooked Hillary Clinton."

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