Both the Senate and House versions of the measure would give President George W. Bush much of the money he requested. But the bills differ over what portion should go to military operations.
The Pentagon says it needs the money by the first week of May, so Senate and House negotiators are expected to act quickly to send the president a final bill.
Other issues to be resolved in the competing versions include immigration changes, a U.S. embassy in the Iraqi capital of Baghdad, military death benefits and the fate of an aircraft carrier.
"I'm confident we will be able to come back with a product, in the form of a conference report, which the Senate can support," said Sen. Thad Cochran, chairman of the Senate Appropriations Committee.
He said the bill gives strong support to troops in the fight against terrorism and provides needed dollars for the State Department.
Overall, the Senate version would cost about $81 billion, compared with the $81.4 billion the House approved and the $81.9 billion that Bush requested.
Congress has passed four similar emergency spending measures for the wars since the attacks of Sept. 11, 2001. This one would put the overall cost of combat and reconstruction efforts in Iraq and Afghanistan — as well as Pentagon operations against terrorists worldwide — past $300 billion.
The nonpartisan Congressional Research Service, says lawmakers previously approved $228 billion. The latest money is to last through Sept. 30, the end of the current budget year. Pentagon officials have said they will have to ask for more money for 2006.
In both the House and Senate, lawmakers struggled to give troops whatever they needed and pay only for projects deemed urgent. Congress was leaving other items to be dealt with in the regular budget for the new budget year starting Oct. 1. In doing so, they were sending a message to the White House that it cannot expect a rubber stamp from Congress on its emergency war-spending requests.
Still, as Bush requested, the bulk of the money — about $75 billion — would go to the Pentagon. The Army and the Marine Corps, the two service branches doing most of the fighting, would get the most.
The House bill would add money to the president's request for defense expenses; the Senate's would not. The Senate version would restore some money the House cut for foreign aid and State Department programs.
The Senate bill also would provide $592 million to build a U.S. embassy in Baghdad. The House bill does not fund the construction of a fortified diplomatic compound.
The Senate added a requirement that the Pentagon report every three months to Congress on how many Iraqi security forces are trained and how many U.S. troops are needed.
The Senate also put in requirement that the Pentagon keep the Navy's fleet of 12 aircraft carriers intact. The Pentagon had proposed scrapping one carrier to save money.