The alliance is nearing the number of troops it needs for Afghanistan, where 47,000 soldiers are part of the NATO-led mission, said NATO Secretary-General Jaap de Hoop Scheffer.

"I'm optimistic that we will leave the summit ... with more troop commitments, which is necessary in Afghanistan," De Hoop Scheffer told CNN. "We're not entirely there yet but I think Bucharest will show that we have made a step forward and we are very close to having what we need as far as our force levels in Afghanistan are concerned."

In a speech to the alliance, U.S. President George Bush called on NATO allies to send more troops to Afghanistan.

"If we do not defeat the terrorists in Afghanistan, we will face them on our own soil," Bush said.

Twenty-five NATO allies and 13 other countries have troop presences in Afghanistan, CNN said. The bulk of the recent fighting has been done by Canadian, British, Dutch and U.S. troops.