WINDOW ROCK, Ariz. (AP) _ Mobil Oil Corp. has removed from its list of possible subcontractors a company whose president referred to the Navajos as a ''vanquished and inferior race'' which has no right to make laws on land that is ''ours by right of conquest,'' Mobil officials said today.

Mobil, which is building oil rigs on the Navajo Reservation in the area of Aneth, Utah, took the action against the Customs Clearing House of Denver after a copy of the letter from the Denver company's president, Ronald Vertrees, was forwarded to Mobil, tribal officials said Monday.

The letter, which criticizes the tribe for enacting Navajo hiring preference laws on the reservation, had been sent to the Office of Navajo Labor Relations.

''Given the historical facts, we consider ourselves to be members of the conquering and superior race and you to be members of the vanquished and inferior race,'' Vertrees wrote.

''We hold your land and property to be spoils of war, ours by right of conquest. Through the generosity of our people, you have been given a reservation where you may prance and dance as you please, obeying your kings and worshiping your false gods,'' he continued.

Vertrees, contacted Monday by telephone, said he had no regrets about sending the letter. ''I don't believe in racial discrimination,'' he said. ''If they want to play that way, they will come out the losers.''

Dorothy Jim, deputy director of the tribe's labor-relations office, said the tribe was informed by Mobil officials that a contract with Vertrees' company had been canceled.

However, Merrily Smith, public affairs manager for Mobil's office in Denver, said the company ''never had a contract'' with Customs Clearing House.

''We heard from them back in November that they weren't going to comply with the Navajo Preference Employment Act of 1985. Mobil then removed them from our approved contract vendors list,'' Ms. Smith said. ''We never had a contract with them in the past and we don't have one now.''

Tribal labor officials said tribal laws require subcontractors to abide by Navajo law if they wish to do business on the reservation.

Vertrees said in the letter that, because his company is based in Colorado, it is not bound by ''pretensions of any other government.''

''We hereby inform you that we do not recognize the legal existence of the so-called Navajo Preference in Employment Act of 1985 or any other part of the so-called Navajo Tribal Code,'' he wrote.

Because the company has a policy of hiring only U.S. citizens, Vertrees said he has directed its personnel office to ''terminate immediately any and all Navajos on our payroll and to hire no more Navajos.''