WASHINGTON, Nov 13 (Reuters) - Afghanistan's geography and socioeconomic conditions will make it hard for the U.S. military there to duplicate policies that helped stem Iraq's insurgency, a senior Pentagon official said on Thursday.

Eric Edelman, undersecretary of defense for policy, said even during Iraq's most violent period, it was clear that Afghanistan would require much longer international attention than Iraq.

"It's not going to be an easy, cookie-cutter transfer" he said of hopes that Gen. David Petraeus, the overall commander of U.S. troops in Afghanistan and Iraq, will be able to apply to Kabul policies that worked in Baghdad.

Edelman told reporters that in contrast to Iraq's huge oil and gas resources, centralized government and well-educated population, Afghanistan has grave poverty, little history of centralized rule and 80 percent illiteracy.

Afghanistan's forbidding terrain and the fact that Taliban and other militants base themselves in rural areas also posed greater challenges to U.S. forces than Iraq's largely urban insurgency, said Edelman.

U.S. President-elect Barack Obama, who takes over in January, has promised to withdraw combat troops from Iraq on a timetable that could be completed in 16 months and to bolster forces battling Taliban and al Qaeda militants in Afghanistan.

Obama has also suggested he was open to talks with more moderate Taliban leaders to explore whether the Petraeus strategy of talking to enemies that is credited with helping turn the situation around in Iraq would work in Afghanistan.

Edelman said efforts at seeking political reconciliation would make sense at some future point, but that the Afghan government should take the lead and "the question is when is that point and to whom do you talk."

Afghan's regionalism and complex ethnic and tribal make-up further muddy the waters when it comes to trying to separate potentially reconcilable groups from hostile foes.

"Iraq is complicated enough. Afghanistan is more complicated," Edelman said of tribal and ethnic divides.

U.S. commanders in Afghanistan have requested 12,000 to 15,000 additional U.S. troops on top of the 31,000 now in Afghanistan and a brigade expected in February.

Edelman, who is retiring and will not serve in the incoming administration, predicted there would be some resistance from U.S. commanders to drawing down troops from Iraq rapidly in 2009, when Baghdad holds three sets of elections.

"There will be a tension between trying to get more U.S. forces to Afghanistan quickly ... and the requirements that the commanders in Iraq feel that they have in order to get through a very important year in Iraq," he said. (Editing by David Alexander and David Storey)