The implementation of a March deal to merge the Kurds' semi-autonomous administration and military into Syria's new Islamist government has stalled, and tensions occasionally erupt into clashes, particularly in Aleppo, which has two Kurdish-majority neighbourhoods.

On Tuesday morning, the Kurdish-led Syrian Democratic Forces said in a statement that groups affiliated with the government "targeted the Sheikh Maqsud neighbourhood with a reconnaissance drone", resulting in "the death of one resident".

It later said the toll had risen to three civilians including two women in "indiscriminate artillery and missile shelling carried out by factions of the Damascus government" on the Sheikh Maqsud and Ashrafiyeh districts.

"The shelling is still ongoing, with the use of drones... direct sniper fire and heavy-weapon fire," the SDF statement said.

Aleppo's Kurdish-majority Sheikh Maqsud and Ashrafiyeh neighbourhoods have remained under the control of Kurdish units linked to the SDF, despite Kurdish fighters agreeing to withdraw from the areas in April.

In a statement carried by state news agency SANA, the defence ministry said the SDF targeted "a number of neighbourhoods in Aleppo city adjacent to the districts it controls".

"The ongoing attacks have resulted in three dead and more than 12 wounded among civilians," it said, also reporting one dead in an attack on an army position.

"The SDF is again proving that it does not recognise the March 10 agreement and is trying to undermine it," the statement added.

- Stalled talks -

The SDF controls large swathes of Syria's oil-rich north and northeast, and with the support of a US-led international coalition, was integral to the territorial defeat of the Islamic State group in Syria in 2019.

Its integration into the state following the ouster of longtime ruler Bashar al-Assad a year ago has proven complicated, and the original March agreement was supposed to be implemented by the end of 2025.

The agriculture ministry said two workers at a research centre were among the dead on Tuesday, while Aleppo provincial authorities said an SDF shell hit the main gate of a hospital in the Bustan al-Basha district.

The SDF also accused factions affiliated with Syria's army of attacking the town of Deir Hafer, around 50 kilometres (30 miles) east of Aleppo, and near the strategic Tishreen Dam to the city's northeast.

The Kurdish-led force affirmed its right to "respond legitimately to these attacks".

On Sunday, SDF chief Mazloum Abdi held further talks with officials in Damascus on integrating the Kurdish-led forces, but state media said no tangible results were achieved.

The Kurds have repeated calls for decentralisation -- which Syria's new Islamist authorities have rejected.

Last month in Aleppo, deadly clashes killed five people, in violence that came after Foreign Minister Hakan Fidan of Turkey -- a close ally of the new authorities -- urged the SDF during a visit to Damascus not to be an obstacle to Syria's stability.