(CNN) -- The commander of the U.S. Marines conducting a push against the Taliban in southern Afghanistan said Wednesday that more Afghan security forces are needed to do the job.
Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, salutes as the bodies of American soldiers return home.
"I'm not going to sugarcoat it. The fact of the matter is we don't have enough Afghan forces. And I'd like more," said Brig. Gen. Larry Nicholson, commander of the 2nd Marine Expeditionary Brigade in Helmand province.
Nicholson briefed reporters at the Pentagon by phone from Afghanistan.
Called Operation Khanjar, the push against the Taliban started Thursday with 4,000 American troops, mostly U.S. Marines, and around 650 Afghan forces.
"I'd like to have every Marine battalion partnered with an Afghan battalion," Nicholson said.
"Imagine if I had 4,000 Marines with 4,000 Afghan forces. I mean, it would ... not even be comparable to ... the relative success that we've had over these first seven days."
Nicholson added that police units aren't as well trained as he would like and he plans to work to improve the quality of those forces, including the opening of a police academy.
Troops are attempting to clear areas and to maintain security in the region ahead of August presidential elections.
Nicholson said the Taliban in large part fled the area and have left "significant weapons caches" that include bomb components.
"I think the Taliban is used to people coming maybe through the area, not staying very long," he said. The military will watch "how they react to the fact that we are staying in large numbers in many of these small towns and areas, that we're going to be here to help the government get on its feet, get its sea legs and that we're going to help support the election."
Strides have been made, Nicholson said, citing the capture of Khan Neshin, the province's southernmost city. He said it fell to the light armored reconnaissance battalion "literally without a fight."
"There were some shots fired by the enemy; none fired by us," he said.
"There's a castle down there, and the origins of the castle date into the 18th century. But there's a castle down there where today the governor of Helmand province, for the first time ever, visited. And he raised a flag," an event that Nicholson called an Iwo Jima moment.
Nicholson also addressed reports that Marines don't have enough water at the end of the logistics line.
"I know that the No. 1 threat to us right now is the heat," he said. "We've got helicopters day and night pushing all manner of logistics, but especially pallets of water to the Marines. ... I am more than confident that we're getting the amount of water they need in a timely manner. No one is going without water."
In other developments in Afghanistan, a U.S. military service member was killed Wednesday, the military said.
The death occurred during a combat reconnaissance patrol in the western Farah province, the military said. Watch U.S. soldiers killed in Afghanistan arrive at Dover Air Force Base »
It marks the ninth U.S. military death in Afghanistan since Monday.
In Britain, Defense Secretary Bob Ainsworth on Wednesday mourned the deaths of seven British soldiers in the past week in Afghanistan and defended the hard-fought mission against Taliban militants.
Since July 1, seven British soldiers have been killed in Afghanistan, including the latest death of a service member in an explosion Tuesday in Helmand province.
Speaking at the Royal Institute of International Affairs in London, England, Ainsworth said that "the nature of the fight" against a "highly adaptable" enemy "means we will take more casualties before we succeed."
He said if Britain leaves Afghanistan, the Taliban -- which in 2001 ruled Afghanistan and harbored the terror network that attacked the U.S. -- "will take control and al Qaeda will return."
Also Wednesday, the U.S. military said a militant was killed and bombs seized during a patrol by Afghan police and coalition troops in southern Afghanistan.
The development took place Tuesday and Wednesday in Uruzgan province, a district that neighbors Helmand.
A combat reconnaissance patrol shot the militant after taking fire from a wooded area. The patrol later discovered and destroyed 21 homemade bombs.