At a White House press conference this week alongside President Sauli Niinisto of Finland, Donald Trump was asked about the United States’ commitment to support Finland in the event of a crisis. The American president said Americans are “always ready to help Finland,” before changing his focus to Finland protecting itself.

“One of the things that is happening,” Trump said, gesturing towards Niinisto, “is you’re purchasing large amounts of our great F-18 aircraft from Boeing, and it’s one of the great planes, one of the great fighter jets, and you’re purchasing lots of other military equipment, and, I think, purchasing very wisely. I know all of the military equipment and I actually agree with everything you purchased.”

Reuters reported that the Finnish leader “looked surprised” during Trump’s comments. Now we know why.

President Sauli Niinisto on Tuesday denied that Finland was buying new fighter jets from American planemaker Boeing, following remarks by U.S. President Donald Trump. […] [Niinisto] later denied the deal with Boeing on his Twitter account and on Tuesday in Washington.

It turns out, Finland is in the market for some new jets, and it’s begun the process of getting quotes from international manufacturers. But despite Trump’s boasts, Finland hasn’t “purchased” jets and military equipment from the United States, at least not recently, and a final decision is still years away.

I’m beginning to think Trump should avoid this subject altogether, because he’s been caught repeating plane-related falsehoods a few too many times.

Earlier this year, for example, the president was caught falsely boasting about lowering the price of a new Air Force One. Trump also claimed he saved taxpayers millions on F-35 fighter jets, and it wasn’t long before we learned that wasn’t true, either.

Or put another way, when Trump starts making plane-related claims, be wary.