run with (the) hare and hunt with (the) hounds

Translations
служить и нашим, и вашим
He tries to run with the hare and hunt with the hounds by supporting both political parties.
Он пытается служить и нашим, и вашим, поддерживая обе политические партии.
Definitions
To try to support or benefit from two opposing sides in a conflict or situation, often in a way that is considered hypocritical or duplicitous.