Clean Diesel Technologies Seeks Licenses for ARIS 2000 Selective Catalytic Reduction; Strong Patent Base Boosts Global Partner Program for Airless Injector.

STAMFORD, Conn. -- Clean Diesel Technologies Inc. (CDT) (OTCBB:CDTI) (AIM:CDT) (AIM:CDTS), a developer of chemical and technological solutions to reduce harmful engine emissions, stated today its intention to step up licensing negotiations with global, tier-one automotive suppliers following strengthened patent protection behind one of its primary commercial technologies - the ARIS(R) 2000 injection system for Selective Catalytic Reduction (SCR) of nitrogen oxides (NOx).

CDT already has a number of active U.S. patents for ARIS(R) 2000's single fluid, flow-cooled injector which removes the need for a separate air supply. Two of those 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, it also enables the introduction of a liquid reagent, such as the widely available reagent Urea, into the exhaust streams of lighter 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., commented: "There is immediate market potential for ARIS(R) 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 seek new business partners and licensees actively - especially in the light truck, van and car markets where historical air-powered injectors have been a cumbersome compromise. Furthermore, as the USA and Asia follow Europe's legislative lead, we believe SCR and ARIS(R) 2000 will develop into truly global solutions."

CDT is showcasing ARIS(R) 2000 to potential licensees at a trade conference in Brussels, June 14-15, 2005: "Euro IV & V Strategies for Buyers & Suppliers" (www.integer-research.com/Products/Conference/ ?ServiceID=69&ckIndustryID=4). (Due to its length, this URL may need to be copied/pasted into your Internet browser's address field. Remove the extra space if one exists.)

About Clean Diesel Technologies Inc.

Clean Diesel Technologies Inc. and its U.K. representative office, Clean Diesel International LLC, is a developer of chemical and technological solutions to reduce harmful engine emissions. Clean Diesel Technologies has patented products that reduce emissions from combustion engines while simultaneously improving fuel economy and power. Products include Platinum Plus(R) fuel borne catalysts, the Platinum Plus Purifier System and the ARIS(R) 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.

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.