Originally published Tuesday, October 9, 2018 at 07:42a.m.

WASHINGTON — U.N. Ambassador Nikki Haley is resigning, The Associated Press has learned.

President Donald Trump tweeted that he has a "big announcement with my friend Ambassador Nikki Haley in the Oval Office at 10:30 a.m."

Congressional and Trump administration officials told the AP that Haley plans to resign. They spoke on condition of anonymity because they weren't authorized to speak on the record ahead of Trump's announcement. They did not provide a reason.

Haley was appointed to the U.N. post in November 2016.

Before she was named by Trump to her U.N. post, Haley was governor of South Carolina, the first woman to hold the post. She was re-elected in 2014.

Haley, a rookie to international politics, was an unusual pick for to be U.N. envoy.

As South Carolina governor, she was outspoken in her criticism of Trump during the 2016 campaign — a stance that effectively disqualified other candidates for top administration positions.

The daughter of Indian immigrants, Haley alluded to Trump in denouncing "the siren call of the angriest voices" who disrespected America's immigrants. Trump tweeted that "The people of South Carolina are embarrassed by Nikki Haley."