My Russian teacher told us that "спасибо" could only be used as "thanks" in return for something that is given to us. So according to her, when we want to reject something, we just have to say "Нет" and saying "Нет, спасибо" would be nonsense as we don't receive anything.
But she was a Russian native speaker from Belarus, so maybe she spoke a different dialect... ?
Nay, it is used that way, too. «Спасибо, не надо» is, probably, the most common way to say that I can think of. Politely thanking for offering, and yet denying, is seen in writing well over a century old. For example:
- Нет, спасибо, водки не хочу больше; налей лучше чайку, коли есть еще! (1881)
- Спасибо, не надо теперь. Я хочу просить тебя о другом деле . . . (1898)
- Не надо… спасибо! Зачем мне есть? (Gorky, 1902)
- Спасибо, не хочу (1902)
- У нас, товарищи, свой хлеб есть, спасибо, не стоит… (1935)
- Нет, пока не нужно, спасибо, папочка. (1943)
- Не пью, спасибо (Schwartz, 1949)
- Приготовить тебе что-нибудь? ― Не надо, спасибо. Уно приготовит. (Strugatsky brothers, 1963)
I found some mid-19th century examples, too.
This has to do with the fact that the 'е' as it exists in the Russian alphabet is actually pronounced as 'yeh'. (Or whatever close approximation I can write it down as). Similarly, 'ё' is pronounced as 'yoh'.
When it shows up in other words, where it is not the main attraction, it is possible that it becomes shorter, and the sound is closer to an English 'e' than the Russian 'е'.
You can find similar information if you scroll down on the following page: https://www.duolingo.com/skill/ru/Alphabet-1
I can recommend reading the Tips & Notes. :3
Oh, even without the app, I find myself breezing by them far too often. It takes constant vigilance for me to read all of them, as I like to just go ahead and do the exercises already.
This has cost me a few days of struggling already when the answer I was looking for was described perfectly well in the bloody notes. You'd think that would teach me, but noo~..
Anyway, glad I could help. Now that you know the true sound of that letter, you might notice that most words that contain it have the 'yeh'-sound more or less visible in the word itself, depending on its position and the amount of emphasis it receives in that particular word.