Option Exercise

1 April 2015

Sirius Minerals Plc

Option Exercise

The Directors of Sirius Minerals Plc (AIM: SXX, OTCQX: SRUXY) ("Sirius" or the "Company") announce the receipt of an Exercise Notice in relation to 1,000,000 share options granted to a consultant in March 2010 which expired on 31 March 2015. The Company shall issue and allot 1,000,000 new ordinary shares of 0.25p per share ("Ordinary Shares") at an exercise price of 6p per share, raising a total of £60,000. The monies will be used for general working capital purposes.

An application has been made for the Ordinary Shares, which will rank pari passu with the Company's existing ordinary shares, to be admitted to trading on AIM with admission expected to take place from 8am on 2 April 2015.

Following the issue of the Ordinary Shares, the Company's issued share capital will consist of 2,146,020,261 ordinary shares. This figure may be used by shareholders in the Company as the denominator for the calculation by which they will determine if they are required to notify their interest in, or a change of interest in, the share capital of the Company under the Financial Conduct Authority's Disclosure and Transparency Rules.

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About Sirius Minerals Plc

Sirius Minerals is a potash development company with properties in the United Kingdom (North Yorkshire) and the United States (North Dakota). Its primary focus is the development of the York Potash Project which has the world's largest and highest grade 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. 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.