President Barack Obama is set to announce his long-awaited strategy for Afghanistan next week.
The White House said the president will unveil the plans Tuesday night in a speech at the U.S. military academy at West Point in New York.
News reports say Mr. Obama is most likely to call for the deployment of at least 30,000 more U.S. troops.
In a message posted on a Taliban Web site Wednesday, the Taliban's reclusive leader Mullah Omar said militants will defeat international troops, regardless of the number deployed.
There are currently 68,000 U.S. troops in Afghanistan.
In other news, NATO says its troops are assisting in the search for a cargo helicopter that is missing in the country.
NATO spokesmen Thursday declined to say where the search is taking place, citing security reasons.
The Netherlands-based firm Supreme Global Services, which handles catering and logistics, chartered the helicopter.
It disappeared this week, but there are conflicting reports about which day it went missing.
Officials in central Afghanistan's Logar province say there were reports Wednesday night of a helicopter making an emergency landing. It was not immediately clear if that was the cargo helicopter reported missing..