UN agencies Thursday called on all parties to the conflict in Syria to facilitate "immediate and uninterrupted humanitarian access to all areas throughout the country".
A second UN aid convoy this week reached the besieged Syrian town of Madaya on Thursday.
The UN delivered urgently needed humanitarian supplies to the besieged communities of Madaya, Foua’a and Kafraya.
In a joint statement, UNICEF and the WHO said: "The access granted for limited deliveries of humanitarian supplies is not enough."
"The immediate lifting of sieges in Syria is required, followed by assessments of health and other needs of the population, the provision of on-site medical and nutritional therapeutic care and the evacuation of the wounded and sick to be treated."
The organizations said their teams had come across distressed and hungry children, along with adults suffering from severe malnutrition.
Children in Madaya had also not been vaccinated against diseases such as polio or measles, the agencies said.
More than four million people live in hard-to-reach areas in Syria, the UN statement said and adding that "siege and the denial of humanitarian access to civilians continue to be used as a tactic of war in violation of international humanitarian law".
© Copyright Andolu Ajansi