Sirius Minerals Regulatory News (SXX)

8 June 2018

Sirius Minerals Plc

Director Declaration

In accordance with Listing Rule 9.6.14 R, Sirius Minerals Plc (the "Company") has been informed that Louise Hardy, a Non-Executive Director of the Company, has been appointed as a Non-Executive Director of Polypipe Group plc with effect from 25 June 2018.

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About Sirius Minerals Plc

Sirius Minerals Plc is focused on the development of the Woodsmith Mine, which will access the world's largest and highest grade polyhalite deposit located in North Yorkshire, United Kingdom. Polyhalite is a unique multi-nutrient fertilizer, which can be used to increase balanced fertilization around the world. Sirius Minerals' shares are traded on the Premium List of the London Stock Exchange. 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.