Rookie question re. avoiding fisticuffs

By ChrisKearton23, in Twilight Imperium

Hello everyone

If two players both have ships in a given system do they always have to fight or can this be avoided through a binding deal (“don’t shoot! I have commodities and promissory notes!”)? The rules for combat say ‘must,’ which is pretty uncompromising, however the rules for deals & transactions seem to imply greater flexibility.

thanks

If the rules explicitly say "must" then you must.