Answer: that the U.S. pay money before talks could begin.
During the "X, Y and Z incident," France and America came close to a war. President Adams had originally appointed a committee of minister in order to engage in discussions with the French. These negotiations were meant to imrpove the relationship between revolutionary France and America. While this was going on, three French ministers (X, Y and Z) imposed three conditions to the U.S.: giving France $12 million, apologize for Adams's recent statements and pay the French foreign minister $250,000. The French requested the money to be paid before talks began.