It is not rude, but saying "You're welcome" or "it's a pleasure" is considered polite.

There are different expectations in different cultures. In England, where I am from, it is very common to say, “your welcome”, or similar when somebody thanks you. On the other hand, when I went to Saint Louis, USA, a few years ago and I noticed that waiters and waitresses would seem to be a bit surprised when I said, “Thank you”, when they served my meal. They simply replied, “sure!”, as if they hadn’t expected to be thanked and didn’t really know what to say in response. I would suggest it’s best to learn a handful of common responses (“it’s nothing”, “you’re welcome”, “my pleasure”). If you’re in a place where people are speaking English, listen out for how others respond and try to mirror this. When in doubt, be as polite as possible: it’s better people think you are excessively polite than think you are being rude.

It's rude if you say "you're welcome" sarcastically after doing something for somebody and not being told "thank you". Otherwise it's always polite.

Where I live, it would be rude if you didn't say, "You're Welcome" or something similar to acknowledge their thanks to you. People may not say it is rude, but they will certainly think it! When you acknowledge people, it is never rude :)

Like other teachers have said, it isn't rude. We often respond to "Thanks" or "Thank you" with a simple phrase: "You're welcome". If it's expressed as an exclamation: "You're welcome!" (raising your pitch), it could be considered a rude remark. However, if someone says "you're welcome" with a genuine smile, this makes my day! There's a famous saying: "If manners maketh the man" - Politeness and social etiquette are extremely important, even if someone doesn't seem to reply positively.