A man walks on the rubble of damaged buildings in the rebel-controlled area of Jobar, a suburb of Damascus Thomson Reuters

Syria's electricity supply was gradually returning after it was cut across the whole country on Thursday and Internet connections were briefly disrupted, state media said.

SANA news agency quoted the electricity minister saying that the network was returning and would be restored to its earlier capacity by midnight. It did not say what caused the cut.

It said earlier that the "electricity work has been cut in all governorates. Attempts to find the cause of the outage have begun."

A Reuters witness confirmed that electricity had been cut in Damascus, and the Syrian Observatory for Human Rights, said that power had been cut in the "vast majority of governorates".

SANA reported the Syria Telecommunications Company as saying Internet services were partially halted "as a result of sudden damage to one of the network hubs and repair teams have been sent to fix it".

Blackouts have become common for Syrians as fighting has raged throughout the country over the last five years, but it is rare for the whole country to be affected.

A ceasefire brokered by the US and Russia has been in place for six days now and has reportedly "greatly reduced" violence even though sporadic clashes still affect some cities throughout the country.