Saudi Aramco said on Wednesday it had signed 17 preliminary deals with U.S. companies with a potential overall value of more than $30 billion, during a visit to Washington by the Saudi Crown Prince. The projects span liquefied natural gas, financial services, advanced materials manufacturing and procurement of materials and services, it said in a statement. Saudi and U.S. officials touted billions in new investments and growing financial ties between the two countries on Wednesday, coinciding with a visit to the White House by Saudi Arabia's de-facto leader Crown Prince Mohammed bin Salman.