General Motors announced Monday it will sink $225 million into the company's assembly plant inSpring Hill, Tennessee.

Production of the Saturn Ion and Saturn Vue, which are now made at the plant outside Nashville, is now scheduled to end in March, said GM spokesman Dan Flores.



"The plant will be closed for several months," added Flores, who declined to say when the Spring Hill site will be ready to build vehicles for GM. "At this point, the actual plan for the plant is still being developed. However, we did want to show that it was our intention to continue building vehicles in Spring Hill."



Last month, GM's board of directors, after a review of market trends, decided to kill plans for a new minivan that was supposed to be built in Spring Hill once production of both the Ion and Vue had ended next year. The decision to kill the minivan project left the Spring Hill plant without a future product, raising the possibility that GM could close the plant permanently in 2008 once GM re-negotiated its contract with the United Auto Workers.



GM officials, however, insisted that while Spring Hill might not necessarily build a Saturn vehicle, it will continue to build GM vehicles in the future. The Saturn Astra, which is replacing the Ion, will be built in Europe and the 2008 Saturn Vue will be built in Mexico .



Flores said he could not say which kind of vehicle is slated for future production. Chances are, however, that it will be a small passenger car or tall wagon that could replace the minivan, according to hints from GM's designers and executives.



Flores said the new investment is contingent on a tax break from the state of Tennessee . However, officials from Tennessee 's state government have indicated that the aid will be forthcoming. The UAW also indicated it is prepared to negotiate a less restrictive local contract with GM in return for new work.