May 30, 2020 | 4:37pm

President Trump had to stop himself from committing the worst etiquette sin of the coronavirus age: going in for a handshake.

The president gestured theatrically when his official military greeter approached him with an outstretched palm Saturday as Trump stepped off Marine One onto the tarmac of Andrews Air Force Base.

“No,” he appeared to say — then patted U.S. Air Force Col. Donald Schmidt on the back.

The two laughed and chatted as they walked side by side — and not quite 6 feet apart — to a waiting Air Force One.

Trump was on his way to Cape Canaveral, Florida, for a rescheduled NASA launch that sent American astronauts into space from U.S. soil for the first time in a decade.