"We continue to look into this case," said deputy State Department spokesman Adam Ereli. "We gave Russia a lot of data to establish the veracity of our contentions.

"We will continue our dialogue with Russia on this issue and would note that cooperation in other areas has continued," he told reporters when asked about weekend reports that cited senior US officials as claiming to have found proof of the allegations.

Ereli would not comment on the reports, but reiterated allegations made by the White House and State Department in the early days of the Iraq war in March that Russian firms had sold equipment to Baghdad in violation of US law and UN sanctions.

"We had information that sensitive Russian-made military equipment had been sold to Iraq before the war and posed a threat to US forces there," he said.

"We told the Russians we took the matter very seriously and we raised the issue with the government numerous times at senior levels," he said, hinting that Moscow's explanations to date had not met US concerns.

"This is a subject of ongoing discussion," Ereli said. "There are a variety of explanations. Our concern ... is to ensure that measures are in place so that this kind of proliferation doesn't happen again."

Earlier Monday, Russian officials decried the weekend reports that quoted senior US officials as saying Washington's allegations had been "corroborated" by discoveries in Iraq.

Deputy Prime Minister Boris Alyeshin told the Interfax news agency that "the government is not aware of cases" where Russian firms had sold arms to Iraq.

"We follow international principles on such matters... I think it's impossible to carry out large deals like this without the government's knowledge," Alyeshin said.

He also criticized the United States for going public with the accusations before informing the Russian side.

"In these cases, it would be nice to share such data with us," he said. "Only in this manner can one build cooperation."

On Friday, a senior US official said that discoveries made during the war, as well as in the months since Baghdad fell in April, "corroborated" US allegations that Russian firms sold satellite jamming devices as well as night-vision goggles to Baghdad.

That official said Moscow's denials of the allegations -- made in the early days of the war -- had been inadequate and had done considerable damage to US-Russia relations.

"Those were very difficult issues, and we never received entirely satisfactory explanations of the evidence that we obtained in the heat of the war," the official told reporters.

"The most I can say is we have corroborated some of that evidence," the official said on condition of anonymity. "The issue is still a sensitive one."

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