Britain is to devote another £9 million of aid to helping the estimated 1.5 million people caught up in the violence in Syria, the Government announced.
International Development Secretary Andrew Mitchell said the money - which more than doubles UK assistance so far - was needed to ease a "desperate situation".
It will help provide six months' emergency food for 82,000 people, shelter for more than 9,000 families in Syria and drugs for 1,000 patients with chronic diseases.
Health, water and sanitation services will also be funded for 4,000 of the refugees who have fled over Syria's borders to escape the fighting as well as security for UN humanitarian operations.
Mr Mitchell said: "Ordinary Syrians are increasingly caught up in a desperate situation.
"Increased levels of violence mean that humanitarian agencies still cannot make a clear assessment of need within the country.
"But the situation on the ground is deteriorating, with large numbers of displaced people both within the country and who have fled across its borders.
"Food and medical supplies are urgently needed.
"Britain is continuing to call for an end to the violence. In partnership with the UN and international community, we call upon the Syrian government to allow immediate, full and unimpeded access for humanitarian agencies."