Baghdad, Iraq ? An al-Qaida lieutenant in custody in Iraq has confessed to masterminding most of the car bombings in Baghdad, including the bloody 2003 assault on the U.N. headquarters in the capital, authorities said Monday.

Sami Mohammed Ali Said al-Jaaf, also known as Abu Omar al-Kurdi, “confessed to building approximately 75 percent of the car bombs used in attacks in Baghdad” since the Iraq war began, according to the interim Iraqi prime minister’s spokesman, Thaer al-Naqib.

In Washington, congressional aides announced Monday that the Bush administration planned to announce today it would request about $80 billion more for this year’s costs of fighting wars in Iraq and Afghanistan.

The request would push the total provided so far for those wars and for U.S. efforts against terrorism elsewhere in the world to more than $280 billion since the first money was provided shortly after the 9-11 airliner attacks on New York’s World Trade Center and the Pentagon.

The package will not formally be sent to Congress until after President Bush introduces his 2006 budget on Feb. 7. But the aides, speaking on condition of anonymity, said White House budget chief Joshua Bolten or other administration officials would describe the spending request publicly today.

Until now, the White House had not been expected to reveal details of the war package until after the budget’s release.

Al-Jaaf was taken into custody Jan. 15 and confessed to 32 car bombings, a government statement said, including the bombing of the U.N. headquarters that killed the top U.N. envoy in Iraq, Sergio Vieira de Mello, and 21 other people.

The suspect, a top lieutenant of al-Qaida’s Iraq leader, Abu Musab al-Zarqawi, also built the car bomb used to attack a shrine in the Shiite holy city of Najaf that killed more than 85 people, including Ayatollah Mohammed Baqir al-Hakim, in August 2003, the statement said.

It said he also assembled the car bomb used in May to assassinate Izzadine Saleem, then president of the Iraqi Governing Council.

Two other militants linked to al-Zarqawi’s terror group also have been arrested. They included the chief of al-Zarqawi’s propaganda operations and one of the group’s weapons suppliers, the government statement said.

Since June 28, when the interim Iraqi government took power, there have been about 70 car bombings reported in or around Baghdad, according to an Associated Press tally. At least 372 people were killed and 1,038 were wounded.

U.S. Army 1st Battalion 24th Infantry soldiers search a building while on patrol Monday in Mosul, Iraq. Iraqi authorities announced Monday that a top lieutenant for Abu Musab al-Zarqawi had confessed to several car bombings in Iraq.