People are planning to act as human shields in an effort to protect the Syrian city of Afrin as the Turkish military and its allied forces prepare to capture the Kurdish-controlled urban centre.

Turkey launched its cross-border operation on January 20 saying it needed to eliminate the Kurdish militia known as the People's Protection Units (YPG), which is backed by the United States, but which Turkey describes as a "terrorist" group.

After weeks of fighting, Turkish soldiers and allied Free Syrian Army (FSA) fighters are now on the outskirts of the city and poised to enter. A number of towns and villages were taken from the YPG on Sunday by Turkey's military and its allies in the north and south of the Kurdish district.

"The speed of the assault has taken everyone by surprise," said Al Jazeera's Alan Fisher, reporting from the border town of Gaziantep. He added that supporters in Turkey were also planning to come and act as human shields in an attempt to prevent an all-out attack on Afrin.

"There were people who said they wanted to help the YPG against the FSA and the Turks, and so they offered themselves as human shields - an offer that was accepted by the YPG. And it's not just people from the Kurdish areas who are going there. We're also hearing reports of women's groups, socialist groups that are also offering their services - to put themselves between the FSA and the Turks and the YPG.

"What the Kurds are saying with this human shield is 'we dare you to consider the humanitarian issues'."

Vulnerable civilians

Over the last 48 hours, Afrin city has reportedly been targeted by Turkish air raids, water has been cut off, and the internet severed.

Turkish President Recep Tayyip Erdogan on Saturday said his forces would be inside Afrin in a matter of days, but for humanitarian reasons, they were taking their time to strategise and prevent civilian deaths.

More than one million people are now in Afrin city and villages around it after fleeing the fighting, according to the Syrian Observatory for Human Rights monitor group.

"We're hearing from people inside the city itself that most houses accommodate four to five families with the number of people who have moved because of this offensive into the city," Fisher reported.

Erdogan said on Sunday Turkish troops and allied Syrian rebels were now just four to five kilometres from Afrin.

Turkey's president said so far 950 square kilometres of the district had been captured during the military offensive. The operation was not to "occupy" but "liberate", he said, and then hand over to residents.

"In the Afrin region, the owners of the lands have started to come back," said Erdogan.

{articleGUID}

In a statement to the UN Security Council on Sunday, the Kurdish council that governs Afrin demanded a response to the Turkish offensive.

"The international community must support the resistance of Afrin people and break silence towards the invasive attacks," it said, calling on the UNSC to establish a no-fly-zone over Afrin.

'Is this friendship?'

Erdogan also denounced NATO on Sunday, accusing the Western military alliance of failing to back Turkey's campaign.

"Hey NATO, with what has been going on in Syria, when are you going to come and be alongside us?" Erdogan said in remarks to supporters in Bolu, a city east of Istanbul.

"We are constantly harassed by terror groups on our borders. Unfortunately, until now, there has not been a positive word or voice. Is this friendship? Is this NATO unity? Are we not a NATO member?"

The YPG has been a key American ally in the fight against the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) in Syria and the operation has raised tensions with Washington and European NATO powers.

Ankara views the group as an extension of the Turkey-based Kurdistan Workers' Party (PKK), which it and other countries describe as a "terrorist" organisation.