Kabul, Afghanistan ? The top U.S. commander in Afghanistan said Tuesday he wants to extend the combat tours of 1,200 soldiers amid rising violence, and Defense Secretary Robert Gates said he was “strongly inclined” to recommend a troop increase to President Bush if commanders think it is needed.

Gates also said Pakistan must act to stem an increasing flow of Taliban fighters into Afghanistan as U.S. military officials cited new evidence that the Pakistani military, which has long-standing ties to the Taliban movement, has turned a blind eye to the incursions.

The prospect of a troop increase in Afghanistan, at the same time Bush is ordering 21,500 more troops into Iraq, raises new questions about the military’s ability to sustain its efforts on two major fronts. There now are about 24,000 U.S. troops in Afghanistan, a level that Lt. Gen. Karl Eikenberry, the senior American commander here, said is the highest since the war began in October 2001.

It also raises questions about the future course of the war in Afghanistan, where the United States increasingly is handing off responsibility to NATO forces.

Of the 31,000 troops here under NATO command, about 11,000 are American. The United States has an additional 12,000 or 13,000 to hunt down al-Qaida terrorists and to train the Afghan army.

The number of insurgent attacks is up by 300 percent since September, when the Pakistani government put into effect a peace arrangement with tribal leaders in the north Waziristan area, along Afghanistan’s eastern border, according to a U.S. military intelligence officer traveling with Gates. The officer discussed the matter on condition of anonymity.

Eikenberry said he had recommended to the Pentagon that 1,200 soldiers from the 2nd Battalion, 30th Infantry Regiment, 10th Mountain Division – which is about halfway through a scheduled four-month tour in eastern Afghanistan – be ordered to stay through the end of the year.

That battalion already is scheduled to deploy to Iraq later this year, an illustration of how stretched U.S. forces are by the two wars.