UK International Development Secretary Justine Greening has highlighted the plight of a “whole generation of Syrian children” – five years on from the start of the conflict.
The Tory minister said the partial ceasefire had offered some respite, enabling deliveries of food, winter clothing and other essential aid to certain besieged areas.
But she stressed it was only a “start”, insisting more needed to be done.
Hundreds of thousands have been killed in the conflict between the Assad regime, extremist groups and moderate opposition groups.
In response to the crisis, the UK has committed £2.3billion since 2012.
Speaking on the five-year anniversary, Ms Greening told the Press and Journal: “For a whole generation of Syrian children, war and displacement is the only life they have ever known or can now remember.
“This is a conflict that has destroyed not only schools and hospitals, but childhoods as well.”
Ultimately only a resumption of peace talks – which began in Geneva yesterday – and a negotiated political solution could bring about an end to the crisis, she said.
But in the meantime, she underlined the importance of speeding up the process of agreeing access to ensure aid workers had a free hand to get help wherever it was needed, regardless of who holds the ground.
Ms Greening hailed last month’s Syria conference in London, when the international community pledged more than $11billion (£7billion), more than has ever been committed for a humanitarian crisis in a single day.
Commitments were also agreed to provide access to education and create at least one million jobs in neighbouring countries so refugees can try to build a life close to home.
She said: “The world spoke with one voice to offer the Syrian people and their children the promise of a better future.
“We pledged that we would stand alongside them now and when the time came to rebuild their country.
“To do anything less would be a betrayal of the people of Syria.”