WASHINGTON (AP) — President Donald Trump is expected to announce he will nominate State Department spokeswoman Heather Nauert to be the next U.S. ambassador to the United Nations.

Two administration officials confirmed Trump's plans Thursday. A Republican congressional aide said the president was expected to announce his decision by tweet on Friday morning.

Trump has previously said Nauert was under serious consideration to replace Nikki Haley, who announced in October that she would step down at the end of this year. If Nauert is confirmed by the Senate, she would be a leading administration voice on Trump's foreign policy.

Still, with Trump, no staffing decision is final until he makes the formal announcement, since he has been known to change course in the past.