Around here ministers are anti-camera for the most part. I've been told 9 out of ten times no flash, banished to the balcony or once told 'no more than 5 shots'.
I always check with them after and they all say they didn't notice me - so I'm helping our profession!
I always tell the B&G what the minister's restrictions are so if there's an issue they can fight it out.
I think next year I'll do a portrait of the minister to send to him afterwards with a TY note and see what business that might bring - gotta be good karma anyway!