A British Army commander has described the withdrawal of troops from central Basra as "an important step".
Lt Col Patrick Sanders took part in the handover of Basra Palace
About 550 soldiers left Basra Palace on Sunday to join 5,000 UK troops based at the city's airport.
Lt Col Patrick Sanders, commanding officer of 4 Rifles Battle Group, who planned the withdrawal, said it was "nonsense" to suggest it was a defeat.
But he admitted the troops could be called back into central Basra if the situation demanded it.
Lt Col Sanders told the BBC the Iraqi security forces had been "impressive" in the period leading up to the withdrawal.
"There's quite a lull in violence at the moment out here.
"The Iraqi security forces have been particularly impressive over the last few months or so, and thanks to that we're enjoying a lull."
Lt Col Sanders also said the troops were in a safer position at Basra Airport than in the palace base, which was hit by mortar and rocket fire 750 times in one month.
"Down in Basra Palace we had a lot of attacks on us during the three-and-a-half months that my battle group were down there.
"There's no doubt the atmosphere here at the airport is slightly lighter than it was down in Basra Palace.
"For reasons of Iraqi pride they'd be loathe to call us [back] in unless it was absolutely necessary and that's very encouraging.
"But if it does become necessary, either because they request it or perhaps because the violence against us resumes, then we will go back into Basra."
Lt Col Sanders also described any suggestion that the withdrawal could be seen as a defeat as "complete nonsense".
He said: "The militias... have thrown just about everything they've got at us.
Some British soldiers wore printed t-shirts with slogans
"They've been unable to engage us in open fighting. We've been able to patrol around the city, at will, on foot, and in vehicles, any place or time of our choosing.
"It's been dangerous, and the level of violence that we've been engaged in and the casualties we've suffered are testament to that.
"But the notion that this is a defeat is nonsense. The prime minister set out some time ago... that by late summer we'd be withdrawing from the palace and we've stuck to that timetable."
But Lt Col Sanders said he could not predict when British forces might completely withdraw from Iraq.
"I don't have any idea how long the United Kingdom will be engaged in Iraq, I think probably as long as is necessary.
"We're not necessarily in the endgame but to paraphrase Churchill, it's the beginning of the end.
"My battle group will leave in late November or early December, and we will be replaced."