Travelling by plane when you're sitting next to someone annoying can be the most exhausting thing in the world.

And that's exactly what one woman experienced when she found that her seatmate on a recent flight was "obnoxious" and rude - as he gave her a "pathetic" seven-word excuse for taking up some of the space she reserved.

The woman, named Allie, shared her frustration in a viral post after a fellow passenger on a flight took up the storage space under her seat, leaving her with nowhere to put her bag. She described the incident as "insane plane etiquette" and said she was baffled by the man's response when she confronted him about it.

She explained that upon boarding the plane, she was surprised to find that the man sitting next to her had occupied the storage area under her seat. When she questioned him about it, his reply was far from satisfactory.

In a post on X, formerly Twitter, Allie wrote: "New insane airplane etiquette just dropped: dude next to me took both of our under-the-seat storage spots. [I said] 'Oh, are these both your bags? ' [and he said], 'Yeah sorry I needed your space too."

Social media users were left stunned by a man's audacious behaviour on a flight, as detailed in a viral post. Many commenters expressed disbelief, with many hoping that Allie had his bags removed and stood her ground against him commandeering her space.

Allie later updated followers, revealing she sought help from a flight attendant who resolved the issue.

The man was widely criticised for his actions, with numerous individuals calling him "obnoxious" and questioning why he didn't simply use the overhead bins for his extra luggage.

One commenter pointed out: "That is both so rude and obnoxious. He does realize that overhead compartments are also an option, right?"

Another shared their disbelief at his nerve: "Needed ... your space ... Uh, did those words being next to each other not clue him into the stupidity and selfishness?"

And a third also posted: "You know, every time I read a story like this I think there is no possible way that somebody has the audacity to do something like this, but yet I've read things like this too many times now to doubt it anymore. This absolutely blows my mind."