Clean Diesel Technologies Seeks Licensees for ARIS® 2000 Selective Catalytic Reduction System

Strong patent base boosts global partner programme for airless injector

Clean Diesel Technologies, Inc. ('Clean Diesel'), a developer of chemical and technological solutions to reduce harmful engine emissions, stated today its intention to step up licensing negotiations with tier one global automotive suppliers following strengthened patent protection behind one of its primary commercial technologies - the ARIS® 2000 injection system for Selective Catalytic Reduction (SCR) of Nitrogen Oxides (NOx).

Clean Diesel already have a number of active US patents for ARIS® 2000's single fluid, flow cooled injector which removes the need for a separate air supply. Two of these patents have gone to grant in Europe and a notice of intention to grant has been received on a third fundamental patent providing even stronger IP protection.

Clean Diesel's revolutionary injector not only simplifies SCR installation on heavy duty vehicles but it also enables the introduction of liquid reagent, such as the widely available reagent urea, into the exhaust streams of light duty engines not usually equipped with compressed air systems. This key benefit makes SCR, already the favoured NOx reduction technology, even more attractive to both the Original Equipment (OE) and retrofit diesel engine markets.

Dr. Bernhard Steiner, Chief Executive Officer of Clean Diesel Technologies, Inc. comments: "There is immediate market potential for ARIS® 2000 in Europe where vehicle manufacturers and aftermarket suppliers are looking for compact, cost effective NOx reduction systems to meet emissions regulations such as Euro IV and V. This latest patent allows Clean Diesel to actively seek new business partners and licensees - especially in the light truck, van and car markets where historically air-powered injectors have been a cumbersome compromise. Furthermore, as the USA and Asia follow Europe's legislative lead we believe SCR and ARIS® 2000 will develop into truly global solutions."

Clean Diesel is showcasing ARIS® 2000 to potential licensees at a trade conference in Brussels on 14th - 15th June 2005: 'Euro IV & V Strategies for Buyers & Suppliers.'

Note to Editors

The US patents concerned are no's. 5976475 & 6063350.

About Clean Diesel Technologies, Inc.

Clean Diesel Technologies, Inc. is a specialty chemical company with patented products that reduce emissions from diesel engines while simultaneously improving fuel economy and power. Products include Platinum Plus® fuel catalysts, the Platinum Plus Purifier System, and the ARIS® 2000 urea injection systems for selective catalytic reduction of NOx. Platinum Plus and ARIS are registered trademarks of Clean Diesel Technologies, Inc. For more information, visit CDT at www.cdti.com or contact the Company directly.

Clean Diesel International LLC is located in Surrey England, south of London.

Certain statements in this news release constitute “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements involve known or unknown risks, including those detailed in the Company’s filings with the Securities and Exchange Commission, uncertainties and other factors which may cause the actual results, performance or achievements of the Company, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof.