Sirius Minerals Regulatory News (SXX)

For immediate release: 0700hrs, 24 JANUARY 2011

Sirius Minerals Plc

("Sirius" or the "Company")

North Dakota Assay Results

The Directors of Sirius Minerals Plc (AIM: SXX, OTCQX: SRUXY), the globally diversified potash development group, are pleased to announce the company has received the assay results for its initial drill hole conducted on its 100% owned Dakota Salts Project in North Dakota.

While Sirius is still awaiting the finalisation of the technical report and recommendations from North Rim Exploration Limited ("North Rim"), the following observations can be made:

·; The total intersection is interpreted to include the White Bear marker bed (1.57m) followed by 15.05m of interbed halite with 8.69m of Esterhazy Member mineralisation at the base;

·; The total Esterhazy Member intersection was 27.9 ft (8.5 metres) with an average grade of 11.8% K2O;

·; Peak value of K2O within the Esterhazy intersection of 41.0% K2O and 10.3% Carnallite over 1.1 feet (0.34 meters); and

·; The potash mineralisation is in the form of both sylvite and carnallite which is similar to Esterhazy Member type mineralisation seen in the Saskatchewan Prairie Evaporite Formation.

Sirius and its consultants are continuing to review these results and are planning the next stages of its exploration programme which may include additional seismic lines, geochemical and regional studies prior to initiating further drilling.

Chris Fraser, Managing Director of Sirius, commented:

"We are very pleased that our first hole has confirmed the continuity of the Saskatchewan potash beds into North Dakota and more importantly in our Dakota Salts Project. Sirius is now working with its technical team to properly analyse and interpret these results to plan the next phase of our ongoing exploration activities in North Dakota."

Drill Hole Technical Summary

Drilling of the Dakota Salts EBY-1 wellbore in Burke County, North Dakota, USA, began 14 November 2010. The well was drilled to a final depth of 9167 ftKB (KB=Kelly Bushing) or 2794 mKB on 15 December 2010.

Schlumberger Limited was the drilling and safety manager for the project and Saxon Energy Services was the drilling contractor. SAXON 147 was the rig used to drill the well. North Rim was responsible for the Geological Technical Coordination of the project including core retrieval supervision, detailed geological logging and assay sample selection. Boyd PetroSearch, of Calgary Alberta, Canada provided 2D seismic interpretation.

Three inch core was cut from the lower Dawson Bay Formation 8652 ftKB (2637.1 mKB) to part way through the Prairie Evaporite Formation 8978ftKB (2736.5 mKB). Samples were taken in both the Esterhazy Member and the Whitebear potash marker bed. The cores were first cut in half, and one half of the core was sent for geochemical assaying. A total of 54 assays with an average length of 0.8 feet (0.24 metres) were taken over 43.1 feet (13.1 metres) of core for EBY-1. Within the Esterhazy Member a total of 37 samples over 27.9 feet (8.1 metres) were taken with a maximum length of 1.3 feet or 0.38 metres and an average length of 0.75 feet (0.23 metres). These assay samples were collected by North Rim using industry recognized standards.

The samples were forwarded to the Geoanalytical Laboratories at the Saskatchewan Research Council (SRC) in Saskatoon, Saskatchewan on the 21st of December, 2010. The samples were crushed, split, and analysed using SRC's basic potash package (soluble digestion ICP-OES, % weight insolubles and % weight moisture). Quality assurance and quality control measures were strictly adhered to, including the use of standards, blanks and repeats throughout the analyses. SRC is ISO accredited to 17025.

The assay results and technical content of this release have been reviewed by Tabetha Stirrett, P. Geo. of North Rim. Mrs. Stirrett is a Professional Geologist registered in the province Saskatchewan and is a Qualified Person as defined by NI 43-101 and AIM.

A summary of the results is set out in the Annexure.

For further information, please visit the Company's website www.siriusminerals.com. Alternatively please contact:

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 (Yorkshire), North America (North Dakota), and Australia (Queensland and Western Australia).

The Company is additionally progressing ongoing Research and Development initiatives into the secondary uses of salt and potash beds for energy storage and carbon dioxide sequestration.

Incorporated in 2003, Sirius Minerals' shares are traded on the London Stock Exchange's AIM market. Its shares are also traded in North America on the OTCQX through the use of a sponsored ADR facility. Further information on the Company can be found at www.siriusminerals.com.

Glossary of Certain Technical Terms

ANNEXURE