Senior State Department officials and spokesman Jay Greer declined to comment on the warning list circulated in June. But other U.S. officials confirmed its contents.
U.S. officials said the list was compiled by the State Department's Bureau of Economic and Business Affairs and the Treasury Department's Office of Foreign Assets Control, then cabled to State's "procurement executives" in diplomatic posts around the world.
The officials said they did not know whether State had offered its list to other agencies, but added that Defense could easily have devised its own by drawing from internal intelligence and information from other agencies.
"There was a lot floating around on these companies," one official said.
Former officials of the U.S.-led Coalition Provisional Authority, which governed Iraq until this summer, told The Times they did not see any list of air firms suspected of ties to Bout until May. The CIA had raised suspicion about the flights six months earlier.
The State Department made the decision to circulate its warning list after Deputy Secretary of State Richard L. Armitage and Deputy Secretary of Defense Paul D. Wolfowitz were questioned about possible dealings with Bout firms by Sen. Russell D. Feingold (D-Wis.) during a May 18 hearing of the Senate Foreign Relations Committee.
A State official acknowledged to Feingold in a letter two weeks later that the department had "inadvertently" contracted with "air charter services believed to be connected with ... Bout."
Wolfowitz did not answer Feingold's questions until November, when he confirmed the use of suspected Bout air firms in a classified response, sources said.
Feingold said this week that the "apparent lack of Defense supervision over its subcontractors is a real concern."
Lee Wolosky, a former White House National Security official who tracked Bout for the Clinton and current Bush administrations, said the fact that the Pentagon had not devised "an integrated watch list speaks to a lack of communication within the government."
In addition to Air Bas and Irbis, the State Department's warning list named seven suspected Bout-linked firms and cited Bout and three of his aides. Air Bas and Irbis have been cited in U.N. reports as "fronts" for Bout's arms transport network. The list also names Air Cess, a United Arab Emirates firm that operated out of the office that now houses Air Bas. The Times reported in 2002 that Air Cess was one of several suspected Bout-linked firms that supplied cargo planes to the Taliban.
