A leading Republican senator said it probably would take "at least a couple more years" before enough Iraqis are capable of securing their country, a prime condition set by the Bush administration for beginning to withdraw US troops.

"I don't think Americans believe that we should cut and run out of Iraq by any stretch of the imagination," said Sen. John McCain [Images], an Arizona Republican.

"But I think they also would like to be told, in reality, what's going on. And it's going to be at least a couple more years," said McCain, the No. 2 Republican on the Senate Armed Services Committee.

Despite the growing number of Iraqis and US soldiers dying, US officials have said the insurgency is beginning to wane and that progress has been made in Iraq's transition to a democracy. Recent polls show support for the war slipping among Americans.

McCain and Sen. Joseph Biden, a Delaware Democrat, said the U.S. public needs to be told more clearly and realistically the difficult challenges in Iraq.

"I think we should tell people it's not going to be short," McCain said on NBC's "Meet the Press."

"I'd rather say two or three years and be surprised a year from now than say everything's fine and then be disappointed a year or two from now," he said.