In 2004, he rejected an international proposal to end poppy production in Afghanistan through aerial spraying of chemical herbicides, fearing that it would harm the economic situation of his countrymen. Moreover, Karzai's younger brother, Ahmed Wali Karzai – who partially helped finance Karzai's presidential campaign – was rumored to be involved in narcotic deals, which has been rejected. Karzai said that he has sought in writing a number of times, but failed to obtain, proof of allegations that Ahmed Wali was involved in illegal drugs.