Thornberry was promoted to Shadow Foreign Secretary in June 2016 after Corbyn fired Hilary Benn. She held the role of Shadow Brexit Secretary concurrently until Keir Starmer took on the role later that year. She accused Sky News presenter Dermot Murnaghan of sexism after he asked her to name French minister of foreign affairs and international development, Jean-Marc Ayrault and the president of South Korea, which she was unable to do. Following the 2017 general election, she was given the additional role of Shadow First Secretary of State, effectively acting as Corbyn's number 2.