KABUL, Afghanistan — Seven more Western troops were killed in attacks across Afghanistan on Thursday, military officials said, bringing the two-day fatality toll for the NATO force to 13 and illustrating the war’s widening reach.

Combat deaths are running at their highest levels of the 9-year-old war. This year has already been the most lethal for Western troops’ since the U.S. invasion that toppled the Taliban movement.

NATO’s International Security Assistance Force released few details about the latest fatalities. It did not even disclose the nationalities of those killed, and provided only general details about where the deaths occurred.

The largest single fatal incident Thursday was reported in the west of the country, where three troops were killed by a single roadside bomb. National contingents serving in the west, near the Iranian border, include Americans and Italians.

Three more of Thursday’s deaths occurred in the country’s south, two in an insurgent attack and another in a roadside bombing. Yet another fatality took place in Afghanistan’s east, where insurgents often infiltrate from Pakistan’s lawless tribal areas. The majority of the troops in the east are American, but several other NATO nations have forces there as well.

A day earlier, four service members were killed by a single IED, or improvised explosive device, in Afghanistan’s south, considered the insurgency’s heartland. IEDs — low-tech, but sometimes effective even against well-armored vehicles — are the No. 1 killer of Western troops in Afghanistan.

U.S. troop strength in Afghanistan now stands at 100,000, bolstered by a surge ordered by President Obama last December. The bulk of the American forces are in the south, where NATO is attempting to stifle the Taliban in volatile Kandahar and Helmand provinces.

Even as the fighting pushes ahead, so do efforts by the government of Hamid Karzai to broker some kind of political settlement with the Taliban. While no formal negotiations have begun, contacts have been taking place for months.

NATO officials say the Western military is helping to facilitate the informal talks by granting a measure of freedom of movement to Taliban leaders involved.

Meanwhile, the head of a newly formed government council tasked with overseeing any negotiations with the Taliban and other insurgent groups said he believed the reconciliation effort would move forward.

“”We are taking our first steps,”” former Afghan president Burhanuddin Rabbani told a news conference in Kabul.