Reducing the last elements in each crude in two lists.

There are two lists:

list1 = {{1, 2, 4}, {1, 3, 5}, {2, 5, 7}};
list2 = {{1, 2, 7}, {1, 3, 3}, {2, 5, 6}};

How can we reduce the last number of each premium in list2 since list1 as

diff = {{1, 2, 3}, {1, 3, -2}, {2, 5, -1}}