KABUL — After a smoother-than-expected military operation to take the southern Afghan town of Marjah from the Taliban, the U.S. military is aiming to quash Taliban resistance in the Islamist group's spiritual home of Kandahar by the fall, two senior NATO officials said Tuesday.

They added, however, that success in Afghanistan's second-largest city would depend more on evolving political negotiations than on a decisive military campaign like the one that ousted Sunni Muslim militants from the Iraqi city of Fallujah.

"This is not Fallujah. This is not Baghdad," one senior NATO official said. "There is not going to be house-to-house clearing."

Instead, military officials are looking to minimize urban fighting by encouraging political leaders to lead the way.

"The solution to Kandahar will not be done through security," said the other NATO official, who's a senior U.S. military official in Kabul. "It will be enhanced through security. But the change, the real dramatic change for Kandahar, will have to happen politically."

The officials briefed reporters in Kabul in part to counter reports Monday out of Washington that the coalition will start an intense two-month Kandahar military offensive in June.

Both spoke only on the condition of anonymity in order to discuss the developing military operation more freely.

As officials are discovering in Marjah, a farming area with less than 10 percent of Kandahar's population, clearing the Taliban out is easier than establishing a competent and respected Afghan government and keeping the militants out, however. Kandahar is a center of opium trafficking, the local government and police are widely considered corrupt, the provincial governor is a half-brother of Afghan President Hamid Karzai and the army and national police aren't yet able to operate without U.S troops.

The political push to strengthen the weak Afghan government in the area will come in conjunction with a beefed-up American military presence that aims to establish a stronghold in large parts of central Kandahar where no Afghan or coalition forces operate now.

"This is the jewel," the U.S. official said of central Kandahar. "If the Taliban lose effective control of the city — their ability to harass, intimidate and control the outcomes of what happens on the normal days of life in Kandahar — (then) they've lost."

In coming weeks, the American-led coalition will boost the international military force by nearly 45 percent in Kandahar by sending about 3,500 more fighters to the city of some 1 million people.

There already are about 11,000 Afghan police officers and soldiers there working alongside 8,000 members of the international coalition, military officials said.

Coalition forces in Kandahar have started to clamp down on the city by working to close Taliban supply lines and escape routes.

In recent months, coalition forces have arrested or killed about 70 mid- to high-level Taliban leaders in Kandahar, the U.S. official said.

While there's no "D-Day" for launching intensified military operations in Kandahar, the military officials said the goal was to get the upper hand before the monthlong Muslim holiday of Ramadan began in mid-August.

One of the looming complications in Kandahar is the role played by Karzai's half-brother, an influential power broker in the city.

Ahmed Wali Karzai is respected and feared in Kandahar, where he plays a central role in southern Afghan politics and business. He's steadfastly rejected long-standing allegations that he's involved in southern Afghanistan's drug trade, and President Karzai repeatedly has challenged Western officials to produce proof to back up the claims.

"There are plenty of people in Kandahar who say, 'I owe everything to Ahmed Wali Karzai,' " the U.S. official said. "There's plenty of other people who say, 'If we just get rid of the guy, I could finally live the life I want to.' "

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