A group of American advisers led by a small State Department team played an integral part in drawing up contracts between the Iraqi government and five major Western oil companies to develop some of the largest fields in Iraq, American officials say. The disclosure, coming on the eve of the contracts' announcement, is the first confirmation of direct involvement by the Bush administration in deals to open Iraq's oil to commercial development and is likely to stoke criticism. In their role as advisers to the Iraqi Oil Ministry, American government lawyers and private-sector consultants provided template contracts and detailed suggestions on drafting the contracts, advisers and a senior State Department official said. At a time of spiraling oil prices, the no-bid contracts, in a country with some of the world's largest untapped fields and potential for vast profits, are a rare prize to the industry. The contracts are expected to be awarded Monday to Exxon Mobil, Shell, BP, Total and Chevron, as well as to several smaller oil companies. The deals have been criticized by opponents of the Iraq war, who accuse the Bush administration of working behind the scenes to ensure Western access to Iraqi oil fields even as most other oil-exporting countries have been sharply limiting the roles of international oil companies in development. Though enriched by high prices, the companies are starved for new oil fields. American military officials say the pipelines [in Iraq] now have excess capacity, waiting for output to increase at the fields.