Parliament Speaker Reuven Rivlin ordered the markings removed after learning of the practice from a report in the Maariv daily. The newspaper ran a photo Tuesday showing five workers with white helmets, three of them marked. Two of the workers had simple red lines on their helmets, and the third bore a large "X."
About 180 workers, including Israeli Arabs and foreigners, are building a new wing for the Knesset, Israel's parliament. Foreign workers, many from the Far East or Eastern Europe, are not considered a security threat by Israel.
Ahmed Tibi, an Arab legislator, complained of racism. "The Jews know who was marked," he said, an apparent reference to the yellow Star of David emblems Jews had to pin to their clothes during Nazi rule.
Knesset spokesman Giora Pordes said Arab workers who had not yet completed a lengthy security check had their helmets marked, while Arabs who had been cleared wore plain helmets. The markings were meant to allow Arab laborers to begin work immediately, rather than wait three or four months to complete the security check, Pordes said.
Israeli Arabs make up about 19 percent of Israel's population of 6.7 million people. In more than three years of Israeli-Palestinian fighting, tensions between Israeli Jews and Arabs have increased steadily. Arab citizens of Israel have long complained of systematic discrimination by Israeli authorities.
Several Israeli Arabs have been convicted of helping Palestinian militants, though Israeli officials emphasize that such accomplices constitute a tiny majority.
Pordes confirmed that contractor hired by the Knesset was asked to mark some of the Arab workers, either by giving them different work clothes or helmets.
"If someone was hurt than there is nothing to do but apologize. This was not the intention. The intention was to allow people to work honorably," Pordes told Israel Army Radio. "None of them came and said these markings offended them, please give us a different marking."
Rivlin, the Knesset speaker, said the practice was unacceptable under any circumstances. "We cannot allow the use of any markings that could be seen as a differentiation between people on the basis of race, ethnicity and religion," Rivlin said in a statement.