Additional Polyhalite Sales Commitments

10 September 2013

Sirius Minerals Plc

Additional Polyhalite Sales Commitments

· 750,000 tonnes per annum of new sales commitments bringing the total to 2.78 million tonnes per annum

· One of China's largest fertiliser distributors, Sinoagri, enters into 500,000 tonnes per annum memorandum of understanding

· Commitments in place for almost 60% of phase 1 production and discussions ongoing with customers for in excess of full phase 1 production

The Directors of Sirius Minerals Plc (AIM: SXX, OTCQX: SRUXY) ("Sirius" or the "Company") are pleased to announce further progress in the marketing of polyhalite from its York Potash Project.

Sirius has entered into varying types of agreements covering an additional 750,000 tonnes per annum relating to China, Africa and Latin America bringing the total committed tonnes to 2.78 million tonnes per annum.

Chris Fraser, Managing Director and CEO of Sirius, commented:

"These agreements are a further demonstration of the significant global demand for polyhalite from the York Potash Project. Sirius has only been formally marketing polyhalite for nine months, so to have secured agreements covering almost 60% of the initial production target of 5 million tonnes per annum and to be in discussions that could see us potentially over sold is extremely encouraging."

Included within these additional agreements is a memorandum of understanding that has been entered into with CNAMPGC Holdings Limited Corporation ("Sinoagri") for the sale of 500,000 tonnes per annum of polyhalite for 10 years. The terms will be at market price to be agreed at the final contract stage. Sinoagri is one of only two state-run import agencies for potash fertilizers in China and is one of the largest fertilizer distributors in China covering all regions of the country. Further information on the Company can be found at www.sino-agri.net.

In addition, Sirius has signed commitments for an additional 250,000 tonnes per annum pursuant to Framework Sales Agreements with customers in Africa and Latin America on similar terms to other Framework Sales Agreements announced previously.

As summarised in the table below, there are currently agreements and commitments for customers to purchase a total of 2.78 million tonnes per annum of polyhalite from the York Potash Project, including 1.5 million tonnes per annum from customers in China. Discussions are ongoing with customers around the world which, combined with the existing arrangements, would represent more demand than the initial Phase 1 production target of 5 million tonnes per annum. Further progress on securing demand from the market for polyhalite is expected in the near future.

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About Sirius Minerals Plc

Sirius Minerals is a globally diversified potash development company. Its primary focus is to bring on stream major potash mining facilities through the acquisition and development of projects overlying recognised potash deposits. Today it holds properties in the United Kingdom (North Yorkshire) and the United States (North Dakota). 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.