(Reuters) - United Parcel Service reported a decline in second-quarter earnings on Tuesday after subdued package delivery demand and higher costs from its Teamsters labor contract squeezed profits.

The world's biggest package delivery firm by market capitalization posted an adjusted profit of $1.79 per share for the quarter, down from $2.54 a year ago.

(Reporting by Ananta Agarwal in Bengaluru and Lisa Baertlein in Los Angeles; Editing by Maju Samuel)