KK and an A flops and half of stack in the pot?

Early in a tourney, Blinds 25/50, I with 2100 in chips UTG+1 raise to 150 with KK, two seats down get reraised to 400, everyone else folds, I rereraise to 1100, and two seats down thinks for about a minute then calls. Flop has an Ace and no draws for me, pot is 2275 and I have 1000 left. I went allin, he called with AK and I lost. This is a tough situation with most my money in the pot. Is the only correct move, check and fold if he bets?