AUSTIN, Texas (AP) _ Texaco Inc. blasted a state Supreme Court decision upholding the record $11.1 billion award it was ordered to pay Pennzoil Co. and vowed a prompt appeal to the nation's highest court.

The state Supreme Court issued Monday's ruling without a written opinion, saying only that there was no reversible error in the handling of the case by Texas' 1st Court of Appeals in Houston. The appeals court earlier this year upheld the 1985 jury decision, the largest judgment in U.S. history.

Texaco was ordered to pay the money for interfering four years ago in Houston-based Pennzoil's planned merger with Getty Oil Co.

''This refusal to hear our appeal defies both logic and law,'' James W. Kinnear, Texaco's president and chief executive officer, said Monday. ''We will promptly ask the U.S. Supreme Court to review this case.

''The Texas Supreme Court's failure to review this case also raises serious questions about the Texas legal system's ability to meet the constitutional requirement of giving full faith and credit in judicial proceedings to the laws of other states, a basic underpinning of our nation's legal and economic systems,'' Kinnear said.

Pennzoil's chief attorney in the case, Joseph Jamail, said the court did review the case even though it did not hear oral arguments.

''That's some more misinformation put out by Texaco and that is a lie,'' he said in response to Kinnear's statement.

''They literally stole Getty away from Pennzoil and now, to cover up their blunder, they want to abuse our entire judicial system. They ought to be ashamed.''

In its appeal, Texaco had complained that erroneous rulings by the lower courts ''have resulted in Texaco being driven into bankruptcy and to the brink of liquidation.''

Texaco filed for reorganization under Chapter 11 of the U.S. Bankruptcy Code in April to avoid a requirement under Texas law that it post a bond to cover the judgment while it appealed.

While Kinnear pledged to take the case to the U.S. Supreme Court, other avenues are open. Texaco could ask the Texas Supreme Court to reconsider or it could negotiate an out-of-court settlement.

Pennzoil spokesman Bob Harper said his company remains willing to talk.

''We think it is unfortunate that Texaco's management has persisted in its all-or-nothing strategy in this case and has not made a serious effort to satisfy this judgment by settlement at a level which Texaco could easily accommodate and which Pennzoil could justify to its shareholders.

''The last offer we made to Texaco was $4.1 billion prior to (Monday's) ruling,'' he said.

Anita Larsen, a spokeswoman at Texaco headquarters in White Plains, N.Y., said Monday the company always was willing to negotiate on a reasonable economic basis but would not discuss a specific amount.

Ms. Larsen said she did not know when an appeal to the Supreme Court might be filed.

The battle over control of Getty began in December 1983 when Pennzoil offered $100 a share for about 20 percent of Getty stock. On Jan. 6, 1984, Texaco reached an agreement to acquire Getty for $125 a share, later raised to $128.

Pennzoil sued, claiming interference. The company sought $7.53 billion in actual damages and $7.3 billion in punitive damages. The lawsuit resulted in a four-month Houston trial with the jury ordering Texaco to pay Pennzoil $7.53 billion in compensatory damages and $3 billion in punitive damages.

State District Judge Solomon Casseb upheld the judgment in December 1985 and added $600 million in interest for a total of $11.1 billion.

The 1st Court of Appeals upheld the judgment on Feb. 12, reducing the punitive damages by $2 billion. Even with that reduction, the total award is now more than $11 billion including interest.