State Department deputy spokesman Robert Wood said William Burns, the number three at the State Department, will be in Paris on Thursday for talks on Iran with his counterparts from Russia, China, France, Britain and Germany.
Asked if the administration of President George W. Bush could consider any new steps against Iran with only months left, Wood replied: "I'm not going to pre-empt the meeting and talk about what they may or may not come to agreement on.
"But, look, it's a meeting to try to touch base with our counterparts and see how we move forward. We are still very concerned about what Iran is doing," Wood said.
When pressed on whether the administration, which leaves office in January, had any time left to determine how to progress, Wood said the leadership planned to push on during its remaining weeks.
"The administration is in office until noon January 20 so we're going to continue to work the issue because it is that important."
When it was suggested Burns would not be able to push for further sanctions against Iran, Wood told reporters the meeting would consist of talks "about next steps with the dual-track strategy. That's all."
The United States and its European allies have pressed for a third round of UN Security Council sanctions against Tehran but have run into resistance from Russia and China.
Apart from urging sanctions, the six countries have put forward a package of technological, economic and political incentives if Iran suspends uranium enrichment, which they fear Tehran is pursuing to build a nuclear weapon.
Tehran strongly denies the accusation, saying its nuclear programme is aimed purely at producing civilian energy.
Tensions arose late last month within the group of six countries when the United States slapped sanctions on Russia's main arms firm over the alleged sale of sensitive military technology to Iran.
Russian Foreign Minister Sergei Lavrov described the US move as "inadmissible" and warned the sanctions would affect talks between world powers on the Iranian nuclear program.
