Mr. Sorreta is a career diplomat and the Philippine Permanent Representative to the United Nations in Geneva. He was the ambassador to the Russian Federation, and non-resident ambassador to Armenia, Belarus, Kazakhstan and Ukraine.  He was also the Director-General of the Foreign Service Institute, and Assistant Secretary for American Affairs.

At the Home Office, Ambassador Sorreta was Special Assistant to a President, five Secretaries of Foreign Affairs and one Undersecretary for Policy. He was also Director of the Treaties Division, Southeast Asia Division, US Division, and Pacific Division. He negotiated several multilateral and bilateral treaties, including as a lead negotiator for the RP-US Enhanced Defense Cooperation Agreement, and has appeared as Counsel for the Philippines before the International Court of Justice.

In the Foreign Service, he was Deputy Permanent Representative at the Philippine Mission to the United Nations in New York, where he was previously the Legal Adviser and Representative for Disarmament and International Security.  At the United Nations, he Chaired the Special Committee on the Charter of the United Nations and was Vice-Chairman of the First Committee (Disarmament and International Security). He was also the Philippine Sherpa to the Nuclear Security Summit Process.

He held the position of Deputy Chief of Mission at the Philippine Embassy in Washington DC. While in Washington, he negotiated several agreements and appeared before the US House of Representatives on behalf of Filipino WW II veterans.

For his work in foreign policy, he was conferred the Presidential Order of Mabini twice, with the ranks of Kasugo and Dakilang Kasugo. He was also awarded the Medal for International Cooperation by the Russian Government.

He is a graduate of the College of Law of the University of the Philippines and a member of the Philippine Bar.  While in law school, he worked as research assistant on international law for several professors and Justices of the Supreme Court, was captain of the international law moot court team, and was a member of the editorial boards of the Philippine Law Journal and the Philippine Yearbook of International Law.

Ambassador Sorreta has specialized training on international law and diplomacy, including a UN Fellowship in International Law at Columbia Law School and the Hague Academy of International Law External Program. He has also completed courses at the Asian Institute of Management.

Ambassador Sorreta is currently a member of the Asia-Pacific Leaders Network, the Philippine Society for International Law, and the American Society for International Law.

He is a member of the Technical Panel on Political Science of the Commission on Higher Education, Adviser of the Rodolfo C Severino Professorial Chair of Ateneo, and Adviser at the Russian Center of the New Era University.

Ambassador Sorreta was on the faculty of several colleges and universities in the Philippines where he taught international law, diplomatic and consular practice, treaty law, and international relations. He was a lecturer on these subjects at the Foreign Service Institute and for the classes on Mandatory Continuing Legal Education.

Ambassador Sorreta is married with three children.