The law firm Gibson, Dunn & Crutcher on Thursday stopped lobbying on behalf of Saudi Arabia against U.S. legislation affecting oil-producing countries, becoming the latest firm to end ties with the kingdom amid international outcry over the disappearance and suspected slaying of dissident Saudi journalist Jamal Khashoggi.

Three Gibson Dunn lawyers—including partner Theodore Olson Jr.—were named in August on a $250,000 flat-fee lobbying contract for the kingdom, and the advocacy included the preparation of a white paper opposing the passage of the legislation No Oil Producing and Exporting Cartels Act, widely known as NOPEC. The firm also agreed to prepare an op-ed challenging the legislation, along with an in-depth analysis of the bill, introduced this year in the U.S. House of Representatives.