Public international law

We have established a strong public international law practice and can provide advice on international investment law, enforcement, sovereign immunity, sanctions, trade, human rights and boundary disputes.

The public international law experience of our team covers the spectrum of the field ranging from state-state disputes before the International Court of Justice (ICJ) to advising on human rights disputes and matters of sovereign immunity. A notable area is our advice to Governments on international trusts and tax treaties and their application and enforcement.

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

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.

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

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 ‘eminently qualified’ and his work as ‘excellent in every way’. 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

Advising a Government on investment treaty drafting

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

Caribbean Government international investment law advice

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

Government in the Middle East

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

UK-Czech Republic UNCITRAL arbitration

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 administered by the ICSID Secretariat.

Italian energy company ICSID 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.

Energy company UNCITRAL arbitration against Pakistan

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

Defending Greek company in Jordan

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.

Litigation advice for the Ukranian government

We act for the Ukrainian government in relation to a variety of commercial disputes.

Croatian gaming concession arbitration

Acting as Counsel for the respondent in Adria Beteiligungs v The Republic of Croatia, we worked on an UNCITRAL arbitration under the aegis of the Permanent Court of Arbitration related to a gaming concession agreement in Croatia.

Ecuador v Colombia ICJ case

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

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