In Inquiry, Drilling Company Chief Quits LONDON - The chief executive of Saipem, the largest European drilling and engineering contractor for the oil industry, resigned Wednesday evening after an Italian prosecutor's office said it was investigating possible corruption. The executive, Pietro Franco Tali, also served as deputy chairman of the company, in which the big Italian oil company Eni has a controlling stake. A Saipem spokesman, Andrea Pagano Mariano, said the investigation related to contracts on oil and gas projects in Algeria involving the state oil company Sonatrach. He declined to elaborate. Although Mr. Tali "is in no manner a subject of the prosecutor's investigation, he felt that his resignation would better enable the company to respond to the prosector's inquiry," Saipem said in a statement. The activities were said to have occurred through 2009. Eni, which has about 43 percent of Saipem's shares, held an emergency board meeting Wednesday night, according to a news release. In recent days, it said, the board had urged the drilling company's chairman, Alberto Meomartini, "to take immediate remedial actions in managing the situation." Eni's chief financial officer, Alessandro Bernini, who held the same position at Saipem until 2008, also resigned Wednesday, although he "considers that his actions were right and proper," according to an Eni release. An Eni spokeswoman, Erika Mandraffino, said the accusations about Saipem came to Eni's attention a few days ago. She declined to indicate what the inquiry involves in Algeria, where Saipem has billions of dollars" worth of oil and gas operations and drilling contracts, and about 2,600 employees. Saipem's board named the chief operating officer of Eni's gas and power division, Umberto Vergine, to replace Mr. Tali as Saipem's chief. The company also suspended Pietro Varone, chief operating officer of Saipem's engineering and construction unit, following a notice of inquiry from the prosecutor related to the same investigation. Saipem's board also ordered an internal audit using external consultants. "Saipem believes that its business activities have been conducted in compliance with applicable, internal procedures" and its code of ethics, the company said, and has offered its full cooperation to the prosecutor's office. The investigation is a blow to ENI, which under its chief executive, Paolo Scaroni, is working to establish itself as a premier exploration and production company. Earlier on Wednesday, Eni announced a new natural gas discovery off the coast of Mozambique, where the company has become an early leader in staking a position in that country's promising gas reserves. Although Eni stresses that Saipem is independently managed, the two companies are closely intertwined. In an interview on Nov. 19, Mr. Scaroni said that while the company was divesting other noncore assets, he considered Saipem "a major asset." He said that Saipem was "managed at arm's length" because Eni was only "one of the customers" of the engineering company. He said Saipem was the top candidate to build the portion of the proposed South Stream natural gas pipeline from Russia to Eastern and Western Europe, under the Black Sea. Eni, along with Gazprom, is a crucial backer of the project.