In his Independence Day address, President Donald Trump wrongly claimed that the Continental Army "took over the airports" during the Revolutionary War, more than 100 years before the advent of manned aircraft. When asked about the gaffe while departing the White House on Friday, Trump blamed the mistake on a teleprompter malfunction.

"Actually, in the middle of that sentence, it went out. And that's not a good feeling," Trump told reporters on Friday. But he immediately went on to say that he knew the speech so well that he didn't even need a teleprompter.

"I guess the rain knocked out the teleprompter, so it's not that, but I knew the speech very well, so I was able to do it without a teleprompter. But the teleprompter did go out. And it was actually hard to look at anyway because there was rain all over it," he said.

Trump made the historical blunder in his hour-long speech to the American people during his Fourth of July parade in Washington D.C. on Thursday. The address took place at the grounds of Lincoln Memorial during a rainstorm. President Trump was praising the Americans' military efforts in the war against Great Britain, which took place from 1775 to 1783, when the mistake occurred.

"Our army manned the air, it rammed the ramparts, it took over the airports, it did everything it had to do, and at Fort McHenry, under the rockets' red glare, it had nothing but victory," Trump said.

Aviation had not yet existed and would not be used in American military combat until World War I in the early 20th century. Following Trump's speech, the hashtag #RevolutionaryWarAirports was trending on Twitter as many users mocked the president's blunder.

Elsewhere in Trump's speech, the president inaccurately claimed the Battle of Fort McHenry, which ultimately inspired the lyrics of the "Star Spangled Banner," occurred during the Revolutionary War. However, this famous siege in Baltimore took place decades later, as part of the War of 1812.

Trump's "Salute to America" celebration featured military tanks lined up on the National Mall, war plane flyovers and a televised national address. There was also be two firework displays, one from behind the Lincoln Memorial and the other in Potomac Park.

The White House has yet to say exactly how much the Fourth of July event cost, but it has been reported that millions have already been diverted from other federal agencies in order to cover the expenses. One Democrat already threatened to investigate Trump's use of National Park entrance fees to pay for his Independence Day parade.

Amid reports about the high cost of the event, Trump took to Twitter to assure the public that it was not going to be as much money as people think.

"The cost of our great Salute to America tomorrow will be very little compared to what it is worth. We own the planes, we have the pilots, the airport is right next door (Andrews), all we need is the fuel. We own the tanks and all. Fireworks are donated by two of the greats. Nice!" he wrote.