DETROIT — Toyota wants an extension of a federal tax credit that has delivered savings of up to $3,150 to buyers of hybrid cars.

But some of Toyota's rivals — even those that make hybrids — aren't as enthusiastic.

Toyota, the biggest hybrid maker, is the only automaker so far to have reached the 60,000-hybrid-sales limit set by Congress in the legislation that allowed income tax breaks for buying hybrid cars as a way of encouraging fuel savings and cleaner air. The amount of the credit is based on fuel efficiency.

Even though Toyota reached the limit, buyers of its hybrids still get a credit, but it's far smaller and will disappear entirely later this year. Before hitting the limit, Toyota's Prius received the biggest tax break of $3,150. The tax incentive for buying a Prius or other Toyota hybrid fell by half last October and will be cut in half again on April 1.

"The cap should be raised for us to allow us to expand," Jim Press, president of Toyota Motor North America, said in an interview at the North American International Auto Show here. "Demand for Prius declined when there was a step down in hybrid tax credits. We need to have a certain volume to get the mainstream in for economies of scale."

Press also said support of hybrids should go beyond just the tax credits to include moves such as the purchase of hybrid cars for government fleets.

So far, Toyota appears to be largely alone in seeking reauthorization of the subsidies. The Alliance of Automobile Manufacturers, a Washington-based trade group that includes Toyota as a member, hasn't taken a stand on extending the subsidies yet.

What other automakers say: