That project will cost taxpayers another $1.3 billion, only $20 million of which has been put toward the project so far, according to an April report from the Congressional Research Service.

However, two weeks ago Congress approved nearly half that amount to begin construction of the site.

With a staff of about 1,000 Americans and 400 Iraqis, the mission is one of the United States' largest. It is dramatically larger than what came before it in Baghdad: When the United States pulled out of the country after Saddam Hussein invaded Kuwait in 1990, the embassy staff numbered around 50 and had an annual operating budget of $3.5 million.

By comparison, the new U.S. Embassy in Beijing cost $434 million, according to Congress.

The embassy in Iraq will be three times that expensive because it includes not just offices and living spaces but also a power plant. Iraqi electricity remains unreliable, far below demand and vulnerable to sabotage.

President Bush requested $1.3 billion for the embassy not in the State Department's annual budget but in the 2005 "emergency supplemental," the bill intended to cover costs associated with the war.

The request included $690 million for logistical and security costs and $658 million for the construction of an embassy compound to be built on an expedited schedule within two years.

The U.S. Embassy is currently contained within the "international zone," Saddam's sprawling former headquarters on the Tigris River in Baghdad. U.S. personnel occupy three buildings: the Chancery, a former Baathist residence once occupied by the U.S. Army; the Republican Palace, also known as the Four-Head Palace until the Coalition Provisional Authority paid about $35,000 to have the four massive busts of Saddam removed from its roof; and the ambassador's residence.

The new embassy compound will be built within the "international zone" on a site along the river. The Iraqi government wants the Saddam-era buildings back for its own use.

Congress in May approved $748.5 million for "diplomatic and consular programs" and $592 million for embassy security, construction and maintenance in the supplemental appropriation. During a joint conference on the bill, the Senate was able to reverse a bipartisan provision in the House of Representatives' version of the bill, which had zeroed out that request.

"We knew years ago that we were going to need a new embassy, and yet last summer when plans were laid for construction of this particular site it was not included in the omnibus appropriation bill taken up in November. The 2006 budget request which came up in February, no moneys were included in the president's budget request for that as well," complained Rep. Fred Upton, R-Mich., when he spoke on the House floor in March to restrict construction funding.

The inclusion of the embassy costs in the emergency supplemental allows the Bush administration to fund the compound out of deficit spending, rather than having to identify cuts within the State Department or Pentagon budgets to pay for it. It also allows the project to be built swiftly, without the sometimes-cumbersome oversight of the appropriate congressional committees.

The practice of larding the supplemental with expenses that are not strictly "emergencies" allows the White House and Congress to offload billions from the regular budget and pad it instead with pet projects, said Winslow Wheeler, a budget analyst with the Center for Defense Information, at a conference last month. In the meantime, the deficit just keeps getting bigger.

Moreover, by allowing undisciplined supplementals -- which are passed swiftly and without extensive hearings -- Congress is forswearing one of its only ways of influencing U.S. policy and the executive branch. And with billions being spent with little congressional oversight, it sets the stage for contracting abuses.