By P.R. Venkat

SINGAPORE--A unit of state-owned Chinese firm Citic Ltd. and U.S. private-equity firm KKR & Co. Thursday made a formal offer to buy a Singapore wastewater-treatment company in a deal valuing the company at 1.9 billion Singapore dollars (US$1.4 billion).

Citic Environment (International) Co. and KKR announced in November last year that they are forming a joint-venture to buy United Envirotech Ltd., but a formal offer was to be made after certain regulatory approvals including that from the Chinese government authorities.

In a filing to the Singapore Exchange, Rothschild (Singapore) Ltd., the financial advisor to the joint venture company said that "all offer pre-conditions have been satisfied."

United Envirotech provides engineering services for water-treatment systems and has clients such as state-owned firms China Petrochemical Corp., or Sinopec; China National Petroleum Corp. and China National Offshore Oil Corp. Most of United Envirotech's businesses are in China.

KKR, which currently owns about a 29.65% stake in United Envirotech, will sell its shares to the joint-venture company, which will eventually be majority-owned by Citic Environment. Apart from the share stake, KKR owns convertible bonds of United Envirotech, which if converted into shares, would amount to about 10.23%. United Envirotech's chief executive and chief investment officer, who together own a 16.33% stake in the Singapore-listed company, have agreed to support the deal and join the joint venture.

The statement said that the joint venture company currently owns or has got "irrevocable undertakings" for nearly 51% of United Envirotech shares.

The joint venture company is offering to pay S$1.65 for every United Envirotech shares and doesn't intend to raise its offer price.

Shares of United Envriotech are currently on trading halt and they were last at S$1.620 on Tuesday.

Write to P.R. Venkat at venkat.pr@dowjones.com

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