With accent marks:
Не руби́ сук, на кото́ром сиди́шь.
Do not chop the branch you sit on
This proverb is addressed to a person who harms himself by his actions.
The English equivalent of this proverb is "To shoot oneself in the foot".
Other Russian proverbs
Do not look at a given horse's teeth.
Where it is thin, it breaks.
There are no friends for taste and color.
Don't bring your set of rules in a foreign monastery
(lit.) Whoever gets up early, God gives him
Appetite comes with eating.
Eggs don't teach the chicken.
If you are chasing two hares at once, you won’t catch a single one.