Nikki Haley, who is leaving her post as U.S. ambassador to the United Nations at the end of year, was a rookie on the international stage when she was appointed to the position in November 2016. Since then, she has reset U.S. policy on Israel and helped lead the United States' push to impose increasingly severe sanctions against North Korea.

Haley's term was one of both diplomacy and tough policies that were sometimes unpopular at the U.N. But diplomats have praised her uniformly.

Frances's ambassador to the U.N., Francois Delattre, called Haley "one of the most talented, most authentic U.S. government officials that I have ever met."

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"Nikki is a trusted friend and colleague," said Koro Bessho, Japan's ambassador to the U.N. who has worked closely with Haley on sanctions against North Korea. "I look forward to working with her for the rest of the year."

.@nikkihaley has been and continues to be an outstanding Ambassador & great colleague. Led @UN on several important issues, including North Korea & responding to chemical weapons use in Syria & Salisbury. I look forward to working closely with her until the end of her term. pic.twitter.com/4lrkzsxpRr — Karen Pierce (@KarenPierceUN) October 9, 2018

Haley was the first woman named to President Trump's Cabinet. During Haley's tenure, the U.S. withdrew from the Paris climate accord, the Geneva-based U.N. Human Rights Council, the Iran nuclear deal, and the U.N. Educational and Cultural agency (UNESCO). The U.S. also refused to sign the Global Compact on Migration, a set of non-binding rules for safe, orderly and regular migration.

Haley defended those decisions. Last month, before the annual U.N. General Assembly convened, Haley sparred with the new U.N. Human Rights chief, Michelle Bachelet, tweeting: "High Commissioner Bachelet would do better to encourage the Human Rights Council to focus on countries with reprehensible human rights records, several of whom sit on the Council itself."

On Tuesday, Haley listed what she said were the accomplishments of her two terms, including North Korea sanctions, support for Israel, cutting the U.N. budget by $1.3 billion, and focusing on Iran's support of terror groups in the Middle East, as the U.S. defended its withdrawal from the 2015 nuclear deal.

Haley made zeroing in on Iran a flagship part of her role as U.N. envoy. "If we are speaking honestly about conflict in the Middle East, we need to start with the chief culprit: Iran and its partner militia, Hezbollah," she said last spring.

Her condemnation of Iran was supported by Israel. "We appreciate the strong alliance with America and Ambassador Haley's steadfast support for the truth at the U.N.," Israel's U.N. ambassador Danny Danon told CBS News.

As U.S. ambassador to the U.N., Haley traveled to Africa and Central America. On Tuesday, she said one of her accomplishments was that the U.N. imposed an arms embargo on South Sudan in a U.S.-sponsored resolution.

She was also tough on Russia. In mid-September, she called an urgent meeting of the U.N. Security Council to call out Russia for skirting U.N. sanctions.

Despite tensions between the U.S. and Russia, particularly at the U.N., Russia's ambassador, Vassily Nebenzia, said, "I regret that she is leaving because we had a good working and personal relationship despite all the differences we were and are having."

"She is a charismatic personality she was a friend to all of us, beyond the doors of the Security Council," Nebenzia said, adding, "We are prepared to work with any ambassador."

Haley was unique in building a bond between the White House and U.N. diplomats. She brought ambassadors of the Security Council to the White House and brought U.S. Cabinet members to the U.S. Mission to the U.N. for briefings. Haley also made the point of attending National Security Council meetings and traveling to Washington, D.C., often.

She has also made a point of praising the first lady as well as Jared Kushner and Ivanka Trump.

In her resignation letter, dated October 3, she made her short-term goal clear: "I expect to continue to speak out from time to time on important public policy matters, but I will surely not be a candidate for any office in 2020."