David Cameron has pledged an additional £1.2 billion to support refugees fleeing Syria's brutal civil war as world leaders gather in London for talks on the crisis.
More than 70 countries will be represented at the conference co-hosted by Britain, Germany, Norway, Kuwait and the United Nations.
The UN is appealing for 7.7 billion US dollars (£5.4 billion) to fund aid operations for the 13.5 million people displaced by the fighting and in need of assistance.
It comes after last year's UN appeal for 2.9 billion US dollars (£2 billion) was 60% under-funded.
Mr Cameron said the latest British contribution - to be delivered over the next four years - will take total UK support since the start of the crisis in 2011 to £2.3 billion and should "set the standard" for the rest of the international community.
The Prime Minister also wants to use the conference to focus support on the neighbouring countries - most notably Jordan, Lebanon and Turkey - which are currently home to 4.6 million displaced Syrians.
He argues that providing opportunities to work and access to services is essential to persuading refugees to remain in the region and preventing another mass influx of people into Europe.
One of the aims of the conference will be to ensure there are school places for all refugee children in the region by 2017 as well helping the host countries to provide places for their own vulnerable youngsters.
Officials said they would also be looking to open up new trade and business opportunities for the host countries - which have been straining under the pressure - so that they will see a boost to their own economies as well as helping the for refugees.
Mr Cameron has been pressing for the European Union to agree beneficial trade agreements similar to that which exists between the United States and Jordan which has generated one billion dollars (£680,000) in trade for Jordan.
"With hundreds of thousands of people risking their lives crossing the Aegean or the Balkans, now is the time to take a new approach to the humanitarian disaster in Syria," the Prime Minister said.
"Today's pledge of more than £2.3 billion in UK aid sets the standard for the international community - more money is needed to tackle this crisis and it is needed now.
"But the conference I am hosting today is about more than just money. Our new approach of using fundraising to build stability, create jobs and provide education can have a transformational effect in the region - and create a future model for humanitarian relief.
"And we can provide the sense of hope needed to stop people thinking they have no option but to risk their lives on a dangerous journey to Europe."
Among the key figures attending the conference will be UN secretary general Ban Ki-moon, German chancellor Angela Merkel and US secretary of state John Kerry as well as the Iranian foreign minister Mohammad Javad Zarif and representatives of Russia and China.
Mr Cameron is expected to take the opportunity to discuss his EU reform plan in bilateral meetings with European leaders attending the event, including Belgian prime minister Charles Michel, Greek premier Alexis Tsipras and Slovakia's Robert Fico.