U.S. diplomats have been asked by Washington to gather detailed financial data on their foreign counterparts, including the kinds of information usually sought by spies, according to diplomatic cables made public on Sunday.

The cables, part of a massive release of secret U.S. dispatches by the activist website Wikileaks, show that U.S. diplomats have been asked to gather foreign diplomats' credit card, frequent flier numbers and iris scans, as well as information on their internet identities and the telecommunications networks they use.

The activities are laid out in dispatches that describe how the diplomats must fulfill their obligations under a previously undisclosed program called the "National Humint Collection Directive." In the intelligence world, "Humint" is an abbreviation for "human intelligence."

U.S. intelligence agencies often have assigned intelligence agents to work overseas under diplomatic cover. But if foreign governments became convinced all U.S. diplomats function as spies, it could put at risk their ability to conduct normal diplomatic activities and increase the odds that they could be expelled for espionage, a retired diplomat said Sunday....