Public international law

We have established a leading public international law practice and advise on international investment law, land and maritime boundary disputes, the law of the sea, sovereign and diplomatic immunity, sanctions, trade law, international environmental law, human rights, international humanitarian law, the law of international organisations and enforcement.

The experience of our team covers the spectrum of the field of public international law, ranging from state-state disputes before the International Court of Justice (ICJ) and ad hoc arbitral tribunals to advising on human rights disputes (including before U.N. committees) and international law in national courts.

We have an established investor-state arbitration practice with numerous investment treaty arbitration cases, including under the auspices of ICSID and the PCA, representing both international investors and sovereign states. We also have a leading specialist practice advising a number of Governments on drafting investment treaties and investment legislation, a rare specialism in private practice in the field of public international law.

The team includes Hussein Haeri who has over a decade of experience of practicing public international law in London, Paris and New York. His experience includes acting as counsel on state-state disputes such as before the ICJ. It also includes contentious and advisory work on international energy law, international environmental law, human rights, international humanitarian law and the law of the sea. Hussein has extensive experience advising Governments on treaty and legislation drafting and interpretation. He has also acted on matters of public international law in domestic courts, including in the Court of Appeal of England and Wales and the Supreme Court of the United States. Aniruddha Rajput, a member of the United Nations Law Commission, brings to the team extensive academic and professional experience in public international law.

‘The nexus between public international law and commercial issues for both Governments and multinational corporations continues to expand rapidly’, Hussein Haeri explains, ‘with the result that specialist public international law advice is increasingly needed and sought’.

The members of our team are fluent in numerous languages, including French, Spanish, Italian, Russian, Arabic and Turkish and are qualified in both common and civil law jurisdictions, with extensive experience working in international organisations and emerging markets. These key factors contribute to the strength our practice. We are able to advise different clients, namely Governments, multinational corporations, international organisations, non-governmental organisations and individuals, in the context of sensitive disputes involving different regions of the world, including in the Middle East, Africa, Asia, CIS countries, Europe and Latin America. Our clients have praised our ‘deep technical knowledge’ and ‘impressive ability to assess and navigate complex legal and factual situations’. They have referred to Hussein Haeri as ‘an exceptional lawyer’, ‘a standout operator’ and ‘a first rate lawyer who blends strategic thinking with excellent client management skills’. They have acknowledged our ‘responsiveness and professionalism’ as being ‘of a very high order’ and appreciated our ‘excellent customer focus’.

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Investment treaty arbitration increasingly utilized

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Hussein Haeri combines deep technical knowledge of investment treaty arbitration with clarity of strategic direction and impressive project management skills. He demonstrates excellent customer focus and sound judgement.

Thomas Le Feuvre, Head of International Agreements, Government of Jersey

Withers LLP is ‘a good firm for PIL work’; it has a particular focus on investor-state arbitration, but the practice also advises on enforcement and sovereign immunity issues, as well as human rights. Other notable areas include advising governments on the enforcement of international trusts and tax treaties; and the team has notable Middle East and energy sector expertise. Hussein Haeri is ‘very strong’; he led the representation of a UK investor in an International Centre for Settlement of Investment Disputes arbitration against the Czech Republic.

Legal 500, 2017

Hussein Haeri impresses market commentators with his ‘combination of strong litigation skills with expert knowledge in public international law.

Who's Who Legal, 2017

Meet the team

How the team can help

Track record

• We are currently advising a government in the Middle East on its investment treaty program. Government in the Middle East

• Our client is a leading assistive technology company in an expropriation dispute with the Czech Republic under the UK-Czech Republic bilateral investment treaty. We are representing the Claimant as counsel and advocates in an UNCITRAL arbitration, which is administer by the ICSID Sectretariat. UK-Czech Republic UNCITRAL arbitration

• A dispute over an investment in the energy sector and ICSID investment treaty arbitration claim against a European state, Our client is seeking damages for breach of fair and equitable treatment, expropriation and other treaty standards. Italian energy company ICSID arbitration

• Represented a Mauritian energy company as counsel and advocates in an investment treaty arbitration against Pakistan under the UNCITRAL arbitration rules. Energy company UNCITRAL arbitration against Pakistan

• The termination of a 10-year worldwide agency and distribution agreement led to us representing a Greek company in a dispute with a Jordanian state owned enterprise. Defending Greek company in Jordan

• Our litigation team acted in Ecuador v Colombia (Aerial Herbicide Spraying) Counsel of Colombia, in an ICJ case involving issues of international environmental law. Ecuador v Colombia ICJ case

• Conducted an extensive project for a Government client advising them on international investment law issues and drafting an innovative model bilateral investment treaty. Advising a Government on investment treaty drafting

• A Caribbean Government has instructed us to advise on a range of international investment law issues. Caribbean Government international investment law advice

• We are advising a State in relation to discrimination issues arising under a human right treaty.

• We are advising a State in relation to issues pertaining to freedom of navigation and the law of the sea.

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