"Foreign Secretary Liz Truss will arrive in the United States later today for a four-day visit to New York and Washington, the first official visit in his new position," the Foreign Office said.
Truss plans to meet with US President Joe Biden and Vice President Kamala Harris.
She will also take part in the session of the UN General Assembly.
On September 15, British Foreign Trade Secretary Elizabeth Truss took over as Foreign Minister of the Kingdom.
Dominik Raab, who served as Foreign Minister, has been appointed Deputy Prime Minister, Head of the Kingdom's Ministry of Justice.