Final answer:
The agents X, Y, and Z demanded a payment, loan, and bribe from the United States before negotiations could take place. This demand, known as the XYZ affair, turned public opinion against France.
Step-by-step explanation:
The agents X, Y, and Z demanded the payment of $250,000, a loan of $10 million, and a bribe of £50,000 from the United States before any negotiations could take place. This demand came to be known as the XYZ affair, referenced in letters released by President Adams to Congress.
The attempt to extract a bribe outraged the American public and turned public opinion against France. This incident played a significant role in souring relations between the United States and France during this period.
A British political cartoon from 1798, titled 'The XYZ Affair,' depicts the French attempt to force the Americans to pay for the right to negotiate a treaty to ease tensions between the two nations.