Washington (CNN) The United Kingdom appointed a new ambassador to the United States on Friday, more than six months after the previous ambassador resigned following a leak of his private diplomatic cables disparaging the Trump administration.

Amb. Karen Pierce will be the first woman to hold the top envoy spot in Washington. She takes on the role at a challenging time, as the US continues to diverge from its allies on a number of major foreign policy issues and the US and UK chart their bilateral course post-Brexit.

The two countries recently hit a point of contention after the UK's decision to allow Huawei to be a part of its 5G network despite heavy lobbying from the US to ban the Chinese tech company. President Donald Trump "tore into" UK Prime Minister Boris Johnson in a phone call last week after the decision, according to a person familiar with the call.

Pierce is currently the British Ambassador to the United Nations in New York and the Permanent Representative at the UN Security Council.

Foreign Secretary Dominic Raab praised Pierce's appointment to the post, saying in a statement Friday, "We're proud to be sending to Washington such an outstanding diplomat, and I warmly congratulate her on her appointment."

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