I am writing to a client, and I finished my email by:
Please let me know at your earliest convenience.
Do you consider this rude in English culture? I wrote it as an exact translate from my language.
No, that wouldn't be considered rude. Just to elaborate:
The "please" and "your convenience" make it quite polite.
If you said, "I must have an answer now", that would be demanding, if not rude.
That phrasing would be considered polite and professional. It's interesting that it was a direct translation because that's actually a fairly standard way to end a request over email in English business culture.