British troops pulled out of a once restive district in southern Afghanistan on Tuesday after reaching an agreement with tribal elders for Afghan forces to take over security duties.

NATO also announced a new countrywide military operation with Afghan troops designed to maintain pressure on Taliban fighters during the fall and winter and pave the way for long-promised development after the most bitter fighting in five years.

Officials said fighting across Afghanistan killed 44 suspected Taliban militants.

Mark Laity, a NATO spokesman in Kabul, said the decision to withdraw British soldiers from Helmand province's Musa Qala district followed an agreement with tribal elders and the provincial governor and was supported by President Hamid Karzai.

"There has not been any contact with the Taliban and they are not involved in this," Laity said.

CountryWatch: Afghanistan

He said the soldiers were leaving because there hadn't been a major clash in the district in 35 days. Musa Qala was one of the Helmand areas where resurgent Taliban militants put up stiffer resistance than expected when about 4,000 British soldiers deployed to the province last spring.

British Gen. David Richards, commander of the 32,000-strong NATO-led force in Afghanistan, said the shift reflected a success in military operations and added that British troops would still be in nearby districts if the Afghan forces policing Musa Qala needed help.

"We will continue to go back into Musa Qala if the security situation demands it," he said.

Richards also announced the launch of Operation Eagle, but didn't say how many NATO and Afghan soldiers would be involved or the specific areas the country being focused on.

"The underlying purpose of this integrated security operation is to allow and encourage much needed reconstruction and development to take place across Afghanistan," he said.

Richards told reporters NATO forces need to show progress during the next six months to keep the Afghan people's support and prevent the Taliban from taking a stronger hold.

If Afghans don't see measurable improvements this winter, they may choose "the rotten future offered by the Taliban," he said.

At a news conference in London, British Prime Minister Tony Blair called the military efforts in Afghanistan and Iraq important for "the security of the world."

"If we walk away before the job is done from either of those two countries, we will leave a situation in which the very people that we're fighting everywhere, including in extremism in our own country, are heartened and emboldened and we can't afford that to happen," Blair said.

Heavy fighting was reported in several regions of the country Tuesday.

An airstrike by the U.S.-led coalition reportedly killed a suspected midlevel Taliban commander and up to 15 other militants in southern Uruzgan province.

Three 500-pound bombs were dropped on a compound in the Khod Valley in support of a NATO-led operation targeting a group of militants who had previously ambushed NATO and Afghan troops, an alliance statement said. NATO did not identify the Taliban commander.

A five-hour battle between Afghan soldiers and insurgents near the eastern border with Pakistan killed 24 suspected militants and one soldier, said Gen. Mohammed Zair Azimi, the Afghan Defense Ministry spokesman.

The two sides fought with assault rifles, rocket-propelled grenades and heavy machine guns in the Barmal district of eastern Paktika province, Azimi said. He said Afghan soldiers recovered the bodies of those killed and their weapons.

In Helmand's Garmser district, police killed four suspected Taliban and arrested six others, said Ghulam Muhiddin, the provincial governor's spokesman. One policeman was wounded.

In neighboring Kandahar province, suspected Taliban destroyed a tanker truck transporting fuel for NATO-led forces and killed its driver, said Gen. Abdul Raziq, a border police official.

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