US Ambassador to the UN Nikki Haley has announced she is resigning - after nearly two years in the post.
President Donald Trump appeared in the Oval Office alongside Mrs Haley to say she had done "an incredible job".
The 46-year-old former South Carolina governor - one of the few women in the Trump cabinet - gave no reason for her exit, but dismissed speculation she was planning to run for president in 2020.
Mr Trump said he would name a replacement in two-three weeks.
He said he would consider the candidature of Dina Powell - his former deputy security council adviser - and added that his daughter Ivanka "would be dynamite" as ambassador, but that he would be accused of nepotism if he chose her.