A jury in London on Thursday found two former directors of engineering firm Mabey & Johnson Ltd. guilty of making illegal payments to the Iraq government in violation of United Nations sanctions.

The U.K.'s Serious Fraud Office, which prosecuted the case, saidCharles Forsyth and David Mabey inflated contract prices for steel bridges to conceal kickbacks to the Iraqi government under Saddam Hussein. The trial, in Southwark Crown Court, began on Jan. 14. A third defendant, former sales manager Richard Gledhill, pleaded guilty...