The International Committee of the Red Cross (ICRC) on Wednesday (February 21st) asked for access to an opposition enclave near Damascus where a regime aerial campaign has this week killed over 300 civilians and wounded 1,400, AFP reported.

Fresh airstrikes by the Syrian regime on Eastern Ghouta killed at least 24 people Wednesday, including at least three children, and wounded dozens more.

The Syrian Observatory for Human Rights said the latest victims were killed by raids on the towns of Jisreen and Kfar Batna, where it said barrel bombs were used.

"The fighting appears likely to cause much more suffering in the days and weeks ahead, and our teams need to be allowed to enter Eastern Ghouta to aid the wounded," said Marianne Gasser, ICRC's head of delegation in Syria.

Syrian warplanes have this month intensified their strikes on the area, which lies just east of Damascus and is home to around 400,000 civilians.

The unprecedented deluge of bombs unleashed by the regime on Eastern Ghouta towns has caused massive destruction and loss of life.

Access to the area has been restricted, and only one aid convoy has been allowed in this year.

The ICRC said the scope of the catastrophe was such that its medical teams should be allowed inside to assist local doctors and nurses who have been completely overwhelmed.

"Wounded victims are dying only because they cannot be treated in time," Gasser said.

Six hospitals have been struck over two days in Eastern Ghouta, putting three out of service and killing several people, the UN said Tuesday.

"I am appalled and distressed by reports of the horrifying attacks against six hospitals in East Ghouta over the past 48 hours," said Panos Moumtzis, the UN's regional humanitarian co-ordinator for the Syria crisis.

In addition to the six listed by the UN, another key hospital was hit and put out of service Tuesday, the Syrian American Medical Society (SAMS) said.

UN Secretary-General Antonio Guterres on Tuesday said he was "deeply alarmed" by the escalating violence, and urged all sides to uphold the basic principles of humanitarian law, including the protection of civilians.