Former British Prime Minister Keir Starmer announced that he would step down as MP and focus on “international affairs” among other areas, even as his successor Andy Burnham faced lawmakers for the first time in the House of Commons since ousting Mr. Starmer from office in July.

Mr. Starmer, who was Prime Minister for just over two years and an MP for 11 years, represents the central London constituency of Holborn & St. Pancras. In a resignation announcement published on social media, Mr. Starmer said he would now focus on other issues such as international affairs, including defence, security, trade and technology. A former public prosecutor, he said that he would also work to prevent violence against women and girls.

Mr. Starmer said he supported Mr. Burnham and added that he would also back whoever Labour chose as his successor in Parliament, ahead of a by-election for his constituency.