Executive director appointment

2 February 2017

Sirius Minerals Plc

Executive director appointment

Sirius Minerals Plc ("Sirius" or the "Company") announces the appointment of Thomas Staley to the Board as Finance Director.

Thomas Jay Staley, 36, has been with the Company since October 2014, initially as Corporate Development Director and since 10 December 2014 as the Company's Chief Financial Officer ("CFO").

Thomas is responsible for leading the Company's finance team, including in relation to the Stage 1 financing, the results of which were announced on 3 November 2016. Thomas has over ten years of experience developing and financing energy, resource and infrastructure projects across a range of international markets. His core competency is structuring commercial arrangements and financing projects utilising a wide range of capital including project and export credit backed debt, mezzanine debt and equity.

During his career prior to joining the Company Thomas has worked for Origin Energy and Babcock & Brown in Australia and Mubadala Development Company in Abu Dhabi. In addition to his broad financing experience, he was previously responsible for the financial and governance oversight of Origin Energy's portfolio of International Development projects.

Russell Scrimshaw, Chairman of Sirius said:

"On behalf of the directors we would like to welcome Thomas to the board. Thomas has demonstrated his strong capabilities as CFO over the last two years but especially in the delivery of the Company's Stage 1 financing. His financing and governance experience with projects over his career brings valuable experience and we are delighted to add him to our board."

He currently holds no other directorships and has a beneficial interest in 572,400 ordinary shares in the Company representing 0.01% of the issued share capital of the Company. In addition to this Thomas has 3,086,944 options over ordinary shares in the Company at an exercise price of 29.2p and the contractual right to 2,000,000 ordinary shares, 1 million of which have vested, which become issuable on the achievement of certain milestones and conditions.

There is no further information regarding Thomas Staley that is required to be disclosed under Schedule Two, paragraph (g) (i)-(viii) of the AIM Rules for Companies.

Regulatory information

For the purposes of MAR and Article 2 of Commission Implementing Regulation (EU) 2016/1055, this announcement is being made on behalf of the Company by Gareth Edmunds, External Affairs Director.

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About Sirius Minerals Plc

Sirius Minerals Plc is the fertilizer development company focused on the construction and development of its North Yorkshire polyhalite project in the United Kingdom. It believes the Project represents the world's largest high-grade known deposit of polyhalite, a multi-nutrient form of potash containing potassium, sulphur, magnesium and calcium. Incorporated in 2003, Sirius Minerals' shares are traded on the London Stock Exchange's AIM market (AIM: SXX). Its shares are also traded in the United States on the OTCQX through a sponsored ADR facility. Further information on the Company can be found at: www.siriusminerals.com.