Throughout the country, the wounded are often denied medical treatment by either government officials or rebels, while hospitals and ambulances remain targets of unlawful attacks, ICRC President Peter Maurer said.
The ICRC is seeking 105.3m Swiss francs ($116.27m) in 2014 for Syria.
Syria accounts for one-tenth of its 1.29bn Swiss franc emergency appeal for 80 countries, the largest in the 150-year history of the independent humanitarian agency.
“Syria will remain a top priority for 2014. Winter is coming with no improvement in sight. More death, injuries and displacement are causing immense suffering and tearing apart families in besieged areas. Many civilians have not had proper access to food, water, medical care or electricity for more than a year,” Maurer told a news conference.
“Despite all our calls to the parties to the conflict to respect people’s rights to medical care without any discrimination, we are not seeing any light at the end of the tunnel,” he said.
In the last four months, the ICRC has been able to increase the number of Syrians it reaches with food and water to about 500,000 from 200,000 previously, according to Maurer.
“Where we haven’t been particularly successful is in increasing our medical activities in Syria, which remain below our expectations,” he said.
Areas of heavy fighting in the western part of Syria, from Aleppo in the north down through Homs, Hama and Damascus to the southern border, as well as the eastern province of Deir al-Zor bordering Iraq, remain virtually off limits, Maurer said.