State incentives offered to Ford to help keep a suburban St. Louis assembly plant open through 2007 are worth $US9 million, Missouri governor Bob Holden said on Monday, according to Dow Jones Newswires.

Holden's office announced on Friday that the car maker plans to keep the Hazelwood assembly plant open, Dow Jones noted, adding that Ford originally planned to close the plant by the middle of this decade.

Ford announced early last year that it planned to close the Hazelwood facility and other plants around the country, citing over-capacity as one reason, the report added.

Dow Jones said the assembly plant employs about 2,600 people and assembles the Ford Explorer, Mercury Mountaineer and Lincoln Aviator.

The incentives could also lead to the assembly plant competing for new production in the future, Holden said in a press release cited by Dow Jones.

The news agency noted that Holden originally planned to call a press conference on Monday to explain the details of the incentive package but a spokesman reportedly said the parties involved want to wait until the United Auto Workers ratify the agreement reached between Ford and the union.

Details of the Hazelwood facility's operation, including the number of jobs and vehicles to be assembled, will be announced by Ford after the UAW votes on the deal, Holden said, according to Dow Jones.

The news agency said the state's incentive package includes job training assistance and Brownfield and Development tax credits while Hazelwood and St. Louis County plan to provide local property tax abatements to help with financing at the plant.