Syria has been at war since 2011, following a crackdown on democracy protests by President Bashar al-Assad.

The conflict morphed over time, drawing in foreign powers and jihadists, killing 500,000 people and displacing half of the population.

Last week, jihadists of the Hayat Tahrir al-Sham group and its allies launched a lightning offensive from northwestern Syria near the Turkish border, wresting swathes of territory from government control including Syria's second city Aleppo.

Syria's Kurds have suffered multiple waves of displacement since 2011 and have again found themselves on the frontlines in the latest violence.

A Syria war monitor said late Sunday that around 200,000 Syrian Kurds were "besieged by pro-Turkey factions" who took over the strategic town of Tal Rifaat and nearby villages in Aleppo province.

On Monday, head of the Syrian Democratic Forces Mazloum Abdi said his US-backed organisation was looking to get Kurds living in Tal Rifaat and other parts of Aleppo out to areas under Kurdish control.

"We are actively coordinating with all relevant parties in Syria to ensure the safety of our people and facilitate their secure relocation... to our safe areas in the northeast of the country," Abdi said in a statement.

"The situation in northwest Syria has developed rapidly and suddenly, with our forces facing intense attacks from multiple fronts," Abdi, the SDF commander in chief, said in a statement.

"Following the collapse and withdrawal of the Syrian army and its allies, we intervened to establish a humanitarian corridor between our eastern regions, Aleppo, and the Tal Rifaat area, with the aim of protecting our people from potential massacres.

"However, the attacks of the armed groups backed by the Turkish occupation have disrupted this corridor."

Abdi said despite the offensive, "our forces continue to resist to protect our people residing in the Kurdish neighbourhoods of Aleppo".