A disagreement between Saudi Arabia's royal family and executives of oil giant Aramco over whether to list its shares in London or New York is delaying progress on its planned 2018 initial public offering, write Ben Dummett, Summer Said and Maureen Farrell for The Wall Street Journal.

Executives at Saudi Aramco want to float the shares on the London Stock Exchange because they are concerned that a US listing would expose the firm to greater legal risks, including potential class-action shareholder lawsuits, according to people familiar with the matter.