Reddit has sided with a man who refused to pay for his new girlfriend's last-minute flight to Europe — a trip the man began planning months before he and the woman even started dating.

"I booked a 2-week vacation to Europe about seven months ago, including flights and lodging. My new [girlfriend] of 5 months said she wants to come with me. I told her I would love that, but she'd have to pay for her own flight," the man wrote in a since-removed Reddit post.

He offered to add his girlfriend to his hotel accommodations and even pay for "food, tours, attractions, etc." However, she would have to cover the $700 airfare.

"She asked me if I could buy her plane ticket, and I told her I did not budget for another plane ticket and that I thought it was already fair for me to pay for other things on the trip for us," he continued.

His girlfriend told him the plane ticket "could be her early anniversary/birthday gift," but when he told her he simply couldn't afford it, she became upset, telling him that he makes more money than her.

"I would love for her to come, but I cannot buy her plane ticket because I did not budget for it, and I have other financial obligations. I told her she either needs to pay for her own ticket, or I'll see her when I come back home," he wrote.

In response, the girlfriend told him he was "selfish," and even threatened to break up with him: "Hopefully, I will still be here when you get back."

Reddit users in the comments section were stunned.

"Who's spending $700 on an 'anniversary' gift or birthday? This is nutty," one user wrote.

"They've been together for five months…. so their anniversary is still seven months away. Rather presumptuous," another commented.

"Your GF is not entitled to that type of spending, but clearly, she thinks she is. Enjoy your vacation. While there, be sure to notice how much more relaxed you are away from this woman," someone else urged the man.

"It's been five months, you're still in the honeymoon phase of getting to know each other, and you just learned two very important pieces of information about her: she believes she is entitled to your money, and she has no problem pulling the emotional blackmail crap when she doesn't get her way ... Pull the plug on the relationship now before you get used to her behavior. It isn't going to get better," another user warned.

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