U.S.-led coalition forces and Afghan police killed 20 suspected Taliban in the latest fighting to hit southern Afghanistan, as NATO on Sunday prepared to take command in the insurgency-wracked region.

Afghan forces also killed six militants in southeastern Paktika province, an Afghan official said.

On Monday, the U.S. anti-terror coalition is to formally hand over control of security operations to a NATO-led force that has deployed about 8,000 mostly British, Canadian and Dutch troops in the south.

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The deployment has coincided with the deadliest upsurge in fighting since U.S.-backed forces ousted the Taliban regime in late 2001 for hosting Usama bin Laden, mastermind of the Sept. 11, 2001, attacks.

On a visit to Afghanistan on Sunday, French Defense Minister Michele Alliot-Marie said many Taliban fighters were crossing from Pakistan to stage attacks.

"We need real cooperation from Pakistan, but it seems very difficult for them. The border is a very difficult region and we ask Pakistan to make some more effort to control it," she told reporters in Kabul.

Pakistan, a key U.S. ally in its war on terrorism, says it does all it can to patrol the porous Afghan border.

On Saturday, a joint force of coalition and Afghan troops killed 20 suspected Taliban militants who had attempted an ambush in Shahidi Hassas district of Uruzgan province, a coalition statement said. There were no casualties among coalition or Afghan forces.

Afghan soldiers and police killed six Taliban fighters and captured eight Sunday during a clash in southeastern Paktika province's Waza Khwa district, said Said Jamal, spokesman for the provincial governor. No further details were available.

In Kandahar province, three militants blew themselves up Saturday as they laid an explosive on a road, said Daoud Ahmadi, a spokesman for the provincial governor. Another suspected Taliban died Sunday when a land mine he was planting north of Kandahar city exploded, Ahmadi said.

Taliban-led fighters have escalated roadside bombings and suicide attacks this year, and have also mounted brazen attacks on several small towns and district police stations — a tactic rarely seen in the previous four years.

International forces, backed by the Afghan army, have meted out a tough response.

Afghan Defense Ministry spokesman Gen. Zahir Azimi said a 50-day operation dubbed Mountain Thrust has resulted in the deaths of at least 613 suspected militants. Some 87 others were wounded and about 300 arrested, he said.

Azimi said between 13 and 16 civilians had also died.

He declined to give details of Afghan and coalition casualties. According to an Associated Press count of coalition figures, at least 19 coalition troops have died in Afghanistan during the same period.

British Lt. Gen. David Richards, commander of the NATO-led International Security Assistance Force, said Saturday that Operation Mountain Thrust would wind down as NATO takes over in the south, but its force will "keep up the tempo" of operations against insurgents.

NATO brings a new strategy to dealing with the Taliban rebellion: establishing bases rather than chasing militants, and is hoping to win the support of local people by creating secure zones where development can take place.

But questions remain whether they can quell the violence enough to allow aid workers to get to work in a lawless and impoverished region, where about a quarter of Afghanistan's huge opium crop is grown.

Azimi dismissed concern that there would not be enough troops on the ground. He said the Afghan army would maintain three brigades of about 3,000 troops each in the southern provinces of Kandahar, Helmand and Zabul, supporting the NATO forces.