They'll always fight for rootspace, which is why it's important to have their own pots.
I'd wait till soil is semi-moist, then take a large spoon (soup spoon) and carefully scoop under one of the the seedlings and it's roots...and transplant to it's own container. Try to be careful of it's neighbor's roots.
Repeat as often as needed till each seedling has it's own pot. Be easy re-potting, but make sure all roots are in contact with the soil. (no air pockets)
The longer you wait, the more the roots will tangle. Some minor breakage isn't the end of the world, but have never lost a seedling to doing this. (you ought to see what I do to re-veg's and bonsai's, lol)