In a televised speech on Thursday, George Bush, the US president, acknowledged that Iraq's government had failed to meet goals for political reconciliation and security.
"In my meetings with Iraqi leaders," he said, "I have made it clear that they must."
The goal of enacting and implementing legislation on so-called de-Baathification was rated satisfactory instead of unsatisfactory, the official said on condition of anonymity.
Such a law has not passed, but General David Petraeus, the US commander in Iraq, said this week that the tentative August 26 power-sharing agreement among leading Iraqi politicians was an encouraging sign.
"This agreement by no means solves all of Iraq's problems, but the commitment of its leaders to work together on hard issues is encouraging," he said.
The latest conclusions largely track an assessment in July which said Nuri al-Maliki's government had made satisfactory gains towards eight benchmarks, scored unsatisfactory on eight others and mixed results on two.
In the new report, the Iraqi government showed movement on only one.
The White House would not confirm contents of the report and has tried to lower expectations about its findings.
Bush is required to report to congress on the Iraqi government's progress towards achieving the 18 goals.
Congress included the 18 benchmarks in a war-spending bill in May.
On Thursday, Dana Perino, White House spokeswoman, said it was too early to show improvements in more areas.
"It has only been 58 days since the last assessment of July 15, which showed the Iraqis are making some progress in many areas, but that in others they are lagging," she said.
"Iraq is still under foreign occupation and Iraqis continue to die in great numbers"
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"While everyone continues to work toward more political reconciliation, we don't expect dramatic differences in the September 15 report compared to the one submitted less than two months ago."
Ryan Crocker, the US ambassador to Iraq, said in a congressional testimony this week that Iraqis are struggling to come to terms with a vicious past in the matter of "de-Baathification".
He said: "They are trying to balance fear that the Baath party would one day return to power with the recognition that many former members of the party are guilty of no crime and joined the organisation not to repress others but for personal survival."