Clean Diesel Technologies, Inc. Files Preliminary Proxy Statement.

STAMFORD, Conn. -- Clean Diesel Technologies, Inc. ("Clean Diesel Technologies" or the "Company") (OTC-BB: CDTI, AIM: CDT/CDTS & XETRA: CDI), a developer of technological solutions to reduce harmful engine emissions, filed its preliminary proxy statement with the Securities and Exchange Commission on April 25, 2007. The proxy statement relates to the Company's Annual Meeting to be held in London on June 7, 2007.

Matters that stockholders of Clean Diesel Technologies will vote upon include: (1) election of directors; (2) ratification of the appointment of the independent registered public accounting firm; and (3) approval of reverse stock split and reduction in the par value and authorized number of shares of common stock.

The Company's objective in requesting approval of the reverse stock split is to facilitate its listing on the American Stock Exchange or another recognized U.S. stock exchange, an undertaking the Company committed to in connection with its December 2006 private placement. Clean Diesel Technologies expects that the reverse split would increase its stock price sufficiently to qualify the Company to apply for listing on such national stock exchange. The reverse stock split provides for one (1) share of common stock for each five (5) shares of common stock held by stockholders. The par value per share would be reduced from $0.05 per share to $0.01 par value per share, a level commonly used by other companies. Further, the proposal provides that the number of authorized shares of common stock capital would be reduced from 45 million to 12 million, a level that has not been reduced in proportion to the 1:5 reverse stock split ratio but to a level that will leave shares of authorized capital available for proper corporate purposes. According to the proxy statement, Clean Diesel Technologies would have approximately 6,439,001 shares issued and outstanding, reserves aggregating 2,615,521 shares for options, warrants and stock subscriptions, and 2,945,478 shares of authorized common stock available for proper corporate purposes after the reverse stock split.

About Clean Diesel Technologies, Inc.

Clean Diesel Technologies, Inc. and its UK Branch office, Clean Diesel International, LLC, is a clean energy and environmental technology company supplying proprietary pollution control systems technologies and products to reduce harmful emissions from internal combustion engines while simultaneously improving fuel economy, resulting in "cleaner air" and reduced "greenhouse gas" emissions. Clean Diesel Technologies has patented technologies and its products include Platinum Plus([R]) fuel-borne catalysts for emission control and fuel economy improvement; catalyzed wire mesh diesel particulate filter technologies to reduce particulate matter and other regulated engine emissions; the ARIS([R]) injection systems for selective catalytic reduction (SCR) for control of nitrogen oxide (NOx) emissions; and the low emission biofuel, Biodiesel Plus[TM] formula. 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 US 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.