Formed in 1919, the International Committee of Bankers on Mexico (ICBM) provides an interesting comparison with the second China consortium. Once again Lamont was the central figure on the American side, and once again the bankers demonstrated that they would act independently of other business interests or the wishes of their government in pursuit of their ends. The ICBM, however, never loomed as large in the plans of the Department of State's Division of Mexican Affairs as the China consortium did in the visions of MacMurray and Hornbeck.
Claiming pressure from European bankers, Lamont solicited the approval of the Department of State for the organization of an international committee of bankers in 1918. In 1919 approval to bring together American, British, and French banking groups concerned with investments in Mexico was granted by the department, with the proviso that control of the committee's policy remain in American hands. Swiss, Dutch, and Belgian banking interests were subsequently given token representation on the committee.
The primary concern of the bankers was to protect the holders of Mexican securities, especially those of the Mexican government. Lamont and his colleagues were at best marginally concerned with the primary issue dividing the U.S. and Mexican governments in 1920: interpretations of Article 27 of the Mexican constitution and its effect on the claims of American oil companies. Fearing debt repudiation, the bankers were unsympathetic to Washington's tactic of withholding recognition from the Mexican government as a means of forcing it to respect the property rights and claims of the oil companies. Whereas the government of the United States wanted all American claims against Mexico to be settled simultaneously, the International Committee of Bankers on Mexico exhibited few inhibitions about negotiating a separate settlement of Mexico's foreign debt.
Restrained initially by the Department of State, Lamont obtained approval to begin negotiations with the administration of Alvaro Obregón in 1921. In June 1922 the Lamont–De la Huerta agreement was reached, recognizing $500 million of indebtedness and arranging for eventual payment. This arrangement paved the way for the Bucareli agreements between the Mexican and United States governments in 1923, ameliorating the differences between the two and leading to recognition of Obregón's regime.
In the years that followed, Mexico had difficulty meeting the schedule established in the Lamont–De la Huerta agreement, and in 1925 Lamont negotiated a new agreement. Payment remained irregular, however, and negotiations between the ICBM and the Mexican government continued throughout the 1920s and 1930s. In 1930 considerable friction arose between Lamont and the U.S. ambassador to Mexico, his former partner Dwight Morrow. Morrow and the Department of State insisted that a separate agreement between the bankers and the Mexican government was contrary to the interests of both the United States and Mexico. Choosing on this occasion to understate the connection between the ICBM and the Department of State, Lamont insisted that he had reached a private arrangement with the Mexican minister of finance and was not asking for the department's consent. Unable to sway Lamont or the Mexican ambassador to the United States, Morrow warned the Mexican government that the United States did not see the agreement with Lamont as a constructive step toward financial stability. The Mexican government capitulated, assuring Morrow it would not submit the agreement to Congress except as a package comprising provisions for all of Mexico's debts. A final settlement between the ICBM and Mexico was not obtained until November 1942 in the Suarez-Lamont agreement ratified by the Mexican congress and the foreign bondholders. Legal problems kept the International Committee of Bankers on Mexico in existence until at least 1948, when its unrecorded demise appears to have occurred. It did not have any political significance after 1930, when it alienated the Department of State. The department was not kept informed of subsequent negotiations between Lamont and Mexican authorities.
The International Committee of Bankers on Mexico resembled the China consortium in that both consisted of groups of bankers from several nations, brought together with the approval of their governments, but ultimately indifferent to the interests of their governments or of other businessmen. The bankers of the ICBM were concerned with their own particularistic interests: any benefit derived from their activities by their governments or other peoples was incidental.
The ICBM differed strikingly from the China consortium in its relationship to the governments of the members' groups. The committee was formed at the initiative of the bankers, and only the government of the United States indicated a deep concern for its activities. There were no international political problems because none of the other countries that were represented had political interests in Mexico. All accepted American hegemony in Mexico, in contrast to the response to Japan's claims to hegemony over Manchuria. The government of the United States had other interests in Mexico and many other ways to exercise influence there. It never saw the committee as an important instrument of policy. After the friction between the Department of State and Lamont in 1930, only the bondholders cared about the future of the committee.