Simply make the Ships belong to the same side than you, or create an Alliance between sides 1 and 2, and the Enemy vessels Side 2 while you are 1.
And of course, uncheck 'show friendlies' on the map, so he won't see the targets without detecting them first. Or, if you want him to see them from the beginning on, leave it checked
They will still drops decoys and go evasive, but won't attack you directly, if they know about your position.