As investigators continued their probe into the scandal-tainted U.N. oil-for-food program in Iraq, the Associated Press learned on Sunday that at least two Swiss trading companies paid kickbacks to secure contracts to buy oil from Saddam Hussein. According to documents obtained by AP, a Geneva-based firm paid a $60,000 illegal surcharge to the Iraqi oil ministry in 2001. The firm, Lakia Sarl, paid the money to an Iraqi-controlled bank account in Jordan in order to obtain a contract for the Iraqi oil. The company is run by Gazi Luguev, a Russian. When Iraq failed to fulfill the contract, Luguev complained to the Iraqi Oil Marketing Organization, or SOMO, and demanded the kickback be returned, copying the correspondence to the United Nations. That correspondence was obtained by the AP.The chief of the U.N. program, Benon Sevan — who investigators say solicited oil allocations from Saddam's regime and opened himself to the appearance of conflicts of interest — then asked SOMO for its comment before reporting the bribe to the U.N. committee which oversaw the program. Sevan's correspondence also was seen by the AP. "Due to your attitude, it is necessary for us to ask the immediate reimbursement of the sum of $60,000 — which was sent to you from us on your request for a so-called 'necessary' advance payment," Luguev said in a fax to SOMO, dated October 2002. The price set for Lakia to pay for Iraqi oil was significantly lower than the market at that time. When contacted by the AP for comment, Luguev said to "call back in 10 minutes." Phones at Lakia's Geneva offices then rang unanswered later Sunday.