"We believe that it's advisable and certainly understandable to take another couple of weeks here to see if we can bring the entire Security Council along on a package, and in that package it would provide a set of choice for the Iranian regime," McCormack said at a news briefing.

McCormack made the remarks after the EU-3, namely Britain, France and Germany, said Tuesday that they are preparing a package of fresh incentives for Iran -- including affordable energy and greater trade with the West -- that would be granted if Tehran resumed negotiations on its nuclear program and agreed to halt the enrichment of nuclear fuel.

U.S. Secretary of State Condoleezza Rice said Wednesday that Washington was ready to wait "a couple of weeks" for the Europeans to make their proposal before pressing for tough UN action.

In two weeks, give or take a day, "there will be some action in the Security Council," McCormack said. "We will see what the action will be."

"We thought that it was a good idea to continue some of the diplomatic discussions for over the next couple of weeks here," the spokesman said.

Washington has been trying to press the UN Security Council to pass a resolution against Iran under Chapter 7 of the UN Charter.

"A Chapter 7 resolution compels countries to change their behavior if they are defying the international community. It has the force of international law," White House spokesman Scott McClellan said last week.