Syrian forces fully besiege rebel-held areas in Aleppo

The Syrian army completely cut off the last remaining rebel-supply route in Syria's northern province of Aleppo, besieging thus the rebel-held areas inside the city, a monitor group reported on Sunday.

The Syrian forces backed by the Lebanese Hezbollah group severed the Castillo road in the northern countryside of Aleppo, which was the last rebel supply route linking northern Aleppo with rebel-held areas inside the city itself.

Now, the rebel-controlled districts in the eastern part of Aleppo city have become completely besieged, said the Syrian Observatory for Human Rights.

The Syrian forces have been on an offensive to close off Castillo since late last month.

The aim was to isolate rebel-held towns in the northern countryside of Aleppo from rebel-held areas inside Aleppo city.

Throughout the first two weeks of July, the rebels, mainly the al-Qaida-linked Nusra Front, have unleashed repetitive attacks to break the government troops' offensive, but failed to curb the momentum of the Syrian army.

Aleppo, strategically located near the borders with Turkey, is Syria's largest city and once an economic hub. It has been a focal point of clashes between the Syrian army and the rebels.

In the summer of 2012, thousands of armed militants stormed residential districts of Aleppo from its countryside, striking the economic nerves of the Syrian government, which has repeatedly accused Turkey of supporting the rebels for undeclared interests in Aleppo.

The rebels captured several districts in eastern Aleppo city and tried repeatedly to expand their presence to government-controlled areas in the west.

The rebels laid siege to western Aleppo districts after cutting the international road to Aleppo in 2014, a siege broken later by the Syrian army, with the help of Hezbollah.

Military experts say the initial aim of the new Syrian army's battles in Aleppo is to lay a siege on the rebel-held areas and cut off their supply lines to force a surrender.

Another aim is to ensure the security of government-controlled areas in western Aleppo and to prevent the militant groups from blocking the main road connecting Aleppo with the Syrian coast and other provinces in central and southern Syria.

Observers say the Syrian military campaign also aims to recapture areas in the northern and southern countryside of Aleppo in the face of Turkey's perceived attempts to establish a safe zone in northern Syria. Endit