The U.S. ambassador to Qatar is leaving the post at the end of the month after three years in Doha.

Ambassador Dana Shell Smith made the announcement on Twitter early Tuesday morning.

1/2 This month, I end my 3 years as U.S. Ambassador to #Qatar. It has been the greatest honor of my life and I'll miss this great country.

— Dana Shell Smith (@AmbDana) June 13, 2017

2/2 I will be announcing my personal Twitter account soon. Keep an eye out!

— Dana Shell Smith (@AmbDana) June 13, 2017

Smith had tweeted criticism of Trump in the past, implying that his comments on the country were making her job more difficult.

Increasingly difficult to wake up overseas to news from home, knowing I will spend today explaining our democracy and institutions.

— Dana Shell Smith (@AmbDana) May 10, 2017

CNBC’s John Harwood tweeted the story a few hours later, saying Smith had "resigned" over President Donald Trump’s severing diplomatic ties with Qatar and undermining the State Department.

US Ambassador to Qatar has resigned days after Trump renewed attacking the country, which undercut State Dept attempt to calm tensions

— John Harwood (@JohnJHarwood) June 13, 2017

The State Department maintains that Smith, who was appointed by former President Barack Obama in 2014, is stepping down after three years as many U.S. ambassadors do.

"Ambassador Dana Smith's assignment as Ambassador comes to an end this month and she will depart Qatar later this month as part of the normal rotation of career diplomats throughout the world," an unnamed official told The Hill.

"We wish her the best as she moves on from the Department of State."

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