SAN FRANCISCO, July 22 (AFP) - The city of Berkeley planned Tuesday to add companies that do business with Nigeria to its long list of boycott targets.

The municipal council was expected to approve the boycott late Tuesday which would rule out most of the United States main oil suppliers, including Shell, Texaco, Mobil and Arco.

"It is possible the city will be limited to purchasing off-brand gasoline, which may be of lower quality leading to the potential for damage to fleet engines and other equipment," said Frances David, treasurer for the city of Berkeley, just outside San Francisco.

Berkeley has banned itself from doing business with companies linked to the military or nuclear industries including IBM, Motorola and Compaq and those who trade with countries accused of human rights abuses, including Tibet and Burma.

Berkeley was the first US city to apply a systematic boycott on companies doing business with apartheid-era South Africa and was followed years later by the entire country.