A top US officer returning from commanding US Marines in Afghanistan's restive southwest emphasized Wednesday that the pullout of foreign troops from the country would be a slow, drawn-out process.

The withdrawal will be "a slow transition, not a lot of bells and whistles, not a lot of parades, because we don't want to attract attention," stressed Major General Richard Mills in remarks to reporters in Washington.

"It's not one morning people are going to wake up and all coalition forces will be gone -- it'll be a slowly thinning out process, so that hopefully one day people will wake up and look around and say 'hey didn't there used to be US Marines around here?'"

Mills, who oversaw operations in the Afghan Helmand and Nimruz Provinces from April 2010 until earlier this month, said that in some areas foreign powers already have "been able to thin out our forces significantly and turn over local responsibility both to the Afghan police and to the Afghan army."

President Barack Obama has pledged to begin a withdrawal in July of the roughly 100,000 American troops deployed in Afghanistan, but officials have yet to say how many forces will be pulled out.

Most senior military leaders are wary of a rapid withdrawal from the country. Since its beginning in 2001 following the September 11, 2011 attacks, the military campaign has become the longest in US history.

"Obviously, if you pull out too early, there's the risk of the insurgency returning," Mills said.

Throughout his whirlwind tour of Washington press briefings and think tanks, Mills also emphasized by partnering with Afghan forces and "with a fairly lengthy timeline in front of us, I think that risk has been significantly mitigated."

On Tuesday, US Defense Secretary Robert Gates said the top NATO commander in Afghanistan General David Petraeus had yet to deliver his recommendations on how many US troops should be withdrawn in July to begin winding down the nine-year-old war.

"I expect that they will be coming in the not-too-distant future," Gates said.

US troops, insisted Gates on a visit to Kabul last month, would be "well-positioned" to start a limited withdrawal in July, paving the way for Afghan forces to take over and eventually take control of security nationwide in 2014, allowing foreign forces to leave.

Mills also reported major progress in his region following a surge of US and allied troops championed by Petraeus.

He said the nearly 30,000 US and coalition troops in the country's south, the Taliban's birthplace, had made great gains in pushing back insurgents and cutting back poppy production, an important source of funding for the Taliban.

Afghan security forces over the last year, Mills noted, have grown "more confident every day and are quite willing to take on that responsibility."

The local troops "understand it's their ultimate responsibility and they understand the end state of the coalition is to have an Afghan security structure in place that can provide security both against internal and external threats," he said.

"They are anxious to arrive at that capability, so every day they are pressing the envelope more and becoming better able to take on those ultimate challenges."