Year of call: 2014
E: mwassouf@3vb.com

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JuniorsPMs@3vb.com

Mark has a broad commercial and public international law practice.

He is frequently instructed as counsel on investment treaty and commercial arbitrations in a number of sectors, including banking, agriculture, oil and gas and telecommunications. He is presently instructed by Bird & Bird LLP on a complex, high-value LCIA arbitration arising out of a series of English law-governed loan agreements. Mark is also acting as sole counsel to an oil & gas major on a LMAA arbitration arising out of a contract for the supply of bunkers to vessels in a Middle Eastern port. Until it settled in September 2017, he was instructed on a very large commercial claim against a regional Middle Eastern government in the oil & gas sector (led by Constantine Partasides QC).

Mark has significant experience acting as counsel in cases and matters involving complex questions of public international law. Mark has advised governments, NGOs and individuals on sovereign treaty obligations. He has acted (as junior to Ben Emmerson QC and to Geoffrey Robertson QC) on a number of matters involving questions of pure public international law, most recently acting as counsel in a complex application to the UN Human Rights Committee submitted under the First Optional Protocol to the ICCPR. Mark has also been instructed as a delegate / rapporteur on two fact-finding missions of the International Bar Association’s Human Rights Institute (the first to Cambodia and the second to Tanzania), which examined the extent to which the countries’ judiciaries were in compliance with their respective treaty obligations.

Mark also has experience of litigation in the High Court. He is presently being led by Christopher Harris in immunity proceedings related to the enforcement of an arbitral award (instructed by A.P. Berkeley). Until the matter settled in May 2017, Mark was part of the counsel team in the Libyan Investment Authority’s claims in the Chancery Division against Société Générale to recover multi-billion dollar sums lost in equity derivative transactions (instructed by Enyo Law LLP).   

Mark speaks fluent Arabic and has a working knowledge of French. He has worked on cases and projects involving a wide range of jurisdictions and has particular experience working on disputes and projects involving the Middle East and North Africa region.

Prior to transferring to the bar in 2014, Mark practised as a solicitor at Freshfields Bruckhaus Deringer LLP in the firm’s international arbitration and public international law group (2009-2013).

Further information about Mark’s practice and recent experience is set out under the tabs below.


“Very articulate. He is regularly instructed by the best firms.” “His penmanship is very strong.”

Chambers and Partners 2018 (International Arbitration, Leading Junior)

“A clear thinker, speaker and adviser in complex international disputes.”

Legal 500 2017 (International Arbitration, Leading Junior)

Mark has over seven years of experience acting as counsel on commercial and investment treaty arbitrations.

Since transferring to the bar, Mark has developed a busy practice acting as counsel in investment-treaty and commercial arbitrations. He has acted as counsel in arbitrations conducted under all the major rules, including the International Chamber of Commerce (ICC), the London Centre for International Arbitration (LCIA), the United Nations Commission on International Trade Law (UNCITRAL) or the International Centre for the Settlement of Investment Disputes (ICSID). 

Mark’s recent investment treaty arbitration experience includes:

  • acting as counsel for the Sultanate of Oman in the case of Attila Doğan Construction & Installation Co. Inc. v. Sultanate of Oman (ICSID Case No. ARB/16/7) (instructed by Three Crowns LLP);
  • acting as counsel for the claimants in the case of Marfin Investment Group Holdings S.A., Alexandros Bakatselos and others v. Republic of Cyprus (ICSID Case No.ARB/13/27) (instructed by Three Crowns LLP); and
  • acting as counsel for the claimants in the case of Champion Holding Company and others v. Arab Republic of Egypt (ICSID Case No. ARB/16/2) (instructed by Dentons LLP).

Mark’s recent commercial arbitration experience includes:

  • acting as counsel to the respondents in a complex and high value commercial arbitration under the LCIA rules between international parties, arising out of a series of English law-governed loan agreements (instructed by Garreth Wong, Bird and Bird LLP);
  • acting as sole counsel to an oil and gas major in a LMAA arbitration arising from contracts for the supply of bunkers to two vessels in a port in the UAE;
  • acting as counsel for the claimants in a multi-billion dollar claim against a Middle Eastern jurisdiction related to contractual rights to the exploitation of oil and gas resources (instructed and led by Constantine Partasides QC, Three Crowns LLP);
  • acting as counsel for a Jersey-based oil and gas investment fund in an UNCITRAL arbitration arising from an English law governed contract with a Canadian exploration and development company (instructed and led by Constantine Partasides QC, Three Crowns LLP); and
  • acting as sole counsel for a Canadian natural resources company, in a potential contractual arbitration (English law governed) under the ICSID Additional Facility arising from a joint venture with a public body in a Middle Eastern country (instructed by Obeidat & Freihat, Jordan).

Mark is developing a commercial litigation practice. Recent highlights of Mark’s commercial court work include acting as counsel for:

  • a sovereign in immunity proceedings related to the enforcement of an arbitral award (led by Christopher Harris);
  • the Libyan Investment Authority in claims in the Chancery Division against Société Générale to recover multi-billion dollar sums lost in equity derivative transactions (instructed by Enyo Law LLP);
  • Gemini Oil & Gas Fund II L.P. in the Queen’s Bench Division, defending against an action brought under section 69 of the Arbitration Act 1996 (led and instructed by Constantine Partasides QC of Three Crowns LLP).

Mark regularly accepts instructions on cases and matters concerning questions of public international law. He has advised states and other organisations on the implications of sovereign treaty obligations and frequently acts as counsel to clients making applications regarding violations of human rights treaties to United Nations treaty-monitoring bodies.

Current and recent highlights of Mark’s public international law work include:

  • acting as counsel (led by Ben Emmerson QC) in relation to a complex UN Human Rights Committee application against Kazakhstan, brought by members of the Kazakhstani-Palestinian Hourani family;
  • advising (as junior to Geoffrey Robertson QC) a Middle Eastern government on the strength of its position, as a matter of international law, in the context of a high profile dispute with neighbouring countries (instructed by Howard Kennedy LLP);
  • advising the Kingdom of Bahrain on compliance with its periodic reporting obligations under the International Covenant on Civil and Political Rights and the Convention against Torture;
  • providing ad hoc advice to the Kingdom of Bahrain on various issues related to domestic legal and political reform in light of the recommendations made by the Bahrain Independent Commission of Inquiry and Bahrain’s international obligations;
  • acting as counsel in Egypt v Ibrahim Halawa and ors (before United Nations tribunals), a case involving applications to the UN Working Group on Arbitrary Detention, the UN Special Rapporteur on Torture and the UN Special Rapporteur on Human Rights and Counter-Terrorism; and
  • acting as junior expert (led by Ben Emmerson QC) on two reports examining the extent to which the Palestinian anti-corruption courts comply with applicable international standards and obligations.

Mark has significant experience of acting as counsel to public inquiries. He is currently instructed as junior counsel on a statutory inquiry in England and Wales (under the Inquiries Act 2005). He also has experience of advising on an international inquiry conducted according to UN rules. Current and recent highlights of Mark’s public inquiries work include:

  • acting as Junior Counsel to the Independent Inquiry into Child Sexual Abuse in England and Wales, with particular responsibility for the investigation into institutional failures in England and Wales associated with offending abroad (in relation to which Mark is the Lead Junior Counsel). The inquiry has a statutory footing and is mandated to examine whether public bodies and other non-state institutions have taken seriously their duty of care to protect children from sexual abuse in England and Wales (instructed by FieldFisher LLP).
  • advising the Royal Court of the Kingdom of Bahrain on the establishment and operation of the Bahrain Independent Commission of Inquiry chaired by Professor Cherif Bassiouni. Mark was part of a legal team which included Tariq Baloch of 3 Verulam Buildings and Amal Clooney of Doughty Street Chambers. The Commission represented the first time any sovereign state has willingly established a national commission composed entirely of international commissioners.