Syrians are sharing pictures of themselves covering one eye in solidarity with a three-month old baby who lost his eye when Bashar al-Assad's regime bombed his home.

Baby Karim lost his mother and was seriously injured in the artillery attack on his besieged hometown in eastern Ghouta, not far from Syria's capital Damascus. He suffered significant scarring to his skull and lost his left eye in the bombing.

Pictures of the seriously injured infant led to an outpouring of grief, with hundreds of people sharing 'one-eyed' photos on social media in solidarity with Karim, along with the hashtags, #SolidarityWithKarim and #StandWithKarim.

To many, Karim is symbolic of the suffering endured by thousands of Syrian children since the start of the conflict in 2011.

In recent months, conditions in eastern Ghouta have rapidly deteriorated as bombing has intensified and food shortages have increased.

Nearly half of the 400,000 people trapped inside the rebel-held region are children, according to Unicef. President Assad's regime has refused to let UN envoys evacuate over 500 people who desperately require medical attention.

"Infants – some of them just one or two months old – will die if evacuation permits are not granted immediately," UN humanitarian chief Mark Lowcock told the Security Council on Tuesday (19 December).

"All that is needed is the green light from the Syrian authorities for these people to go to hospitals just a few miles outside of eastern Ghouta," he said.

France's UN Ambassador Francois Delattre described the situation in eastern Ghouta as "repulsive".

"The regime is starving its population to kill off the opposition," he said. "It's a serious violation of international law and also a huge moral sin, and everyone who has an influence on the Syrian regime should pressure it to put an end to this situation, which is totally unacceptable."

Among those taking part in the social media campaign is Britain's representative to the United Nations, Matthew Rycroft.

He told the UN this week: "It's just a thirty-minute journey from eastern Ghouta to Damascus to receive treatment.

He stressed that for many of the people trapped inside Ghouta "it really is a matter of life and death".

The White Helmets, the volunteer organisation that rescues civilians in Syria's rebel-held areas, also shared a picture to show their support for Karim and other children caught up in the conflict.