Exxon Corp. said Friday it had told Alaskan and U.S. authorities it was exercising its right to terminate the $900 million settlement reached in March over liability in the Valdez oil spill.

The company's action came a day after the Alaska House of Representatives rejected the 10-year deal to reimburse state and federal cleanup efforts that remain from the March 24, 1989, spill in Prince William Sound.Before the Exxon announcement, Alaska Gov. Walter J. Hickel scheduled an afternoon news conference.

On April 25, U.S. District Judge Russel Holland in Alaska threw out another portion of Exxon's settlement with the two governments - a $100 million criminal penalty related to the spill - saying it was "not adequate."

In announcing its decision to give up the portion of the settlement covering civil liability, Exxon said it had not decided whether to seek a new agreement with the governments on a criminal penalty.

"Judge Holland's decision on April 24, 1991, regarding the plea agreement provided us with 30 days to respond," the company said.

The combined $1 billion settlement would have been the largest involving an environmental damage case in U.S. history.

The two governments and the company had until Saturday to decide whether they would go ahead with the civil portion of the settlement. Its rejection on a 27-13 vote in the Alaska House Thursday made the state's acceptance of the deal unlikely.

The House proposed Exxon pay $700 million within one year plus a $500 million criminal fine.

Exxon spokesman Bill Smith said he did not know what the company's next step would be.

The settlement would have required Exxon to pay the millions to restore natural resources damaged in the sound and the Gulf of Alaska. It also would have settled all state civil claims against Exxon and any claims the federal government might have brought.

The company has already spent $2.5 billion cleaning up the area where 11 million gallons of crude spilled from the tanker Exxon Valdez.

The Alaska House passed a resolution rejecting the settlement on a 27-13 vote Thursday.