World leaders have gathered for a donor conference in London in an attempt to raise £6.2bn ($9bn; €8.3bn) for those affected by the war in Syria.
Some 70 leaders are expected to attend theconference, the fourth of its kind, including UK PM David Cameron and German Chancellor Angela Merkel.
They are aiming to raise funds for education and jobs for Syrian refugees.
Hours before the conference was due to begin, peace talks between the Syrian regime and opposition were suspended.
The United Nations-brokered talks in Geneva, which opened just two days ago, were expected to resume on 25 February.
Staffan de Mistura, the UN's special envoy at the talks, admitted there had been a lack of progress but said that the negotiations had not failed.
The £6.2bn being sought on Thursday is made up of a UN appeal for £5.3bn and approximately £900m requested by regional host governments.
Mr Cameron will pledge an additional £1.2bn in new aid from the UK by 2020.
Part of the reason for the record request is the underfunding of previous appeals.Only 43% of the $2.9bn pledged to the UN's 2015 appeal has so far been funded.
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Media captionPeace talks to end Syrian civil war break down
On Monday, officials told Reuters news agency that the European Union would promise €2bn ($2.2bn; £1.5bn) in aid at the conference. It pledged €1.1bn at the last gathering in Kuwait a year ago.
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 children.
Officials said they would also be looking to open up new trade and business opportunities for the host countries, in order to boost their economies and put them in a better position to help refugees.
A coalition of more than 90 humanitarian and human rights groups meeting in London on Wednesday - including Amnesty International, Oxfam and the Malala Foundation - called for better access to education and jobs for refugees in Syria and neighbouring states.
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Media captionBan ki-Moon: London 'Syria' conference must be 'totally different'
Jan Egeland, Secretary General of the Norwegian Refugee Council, said: "Only an end to the fighting and a negotiated political solution will stop the suffering of ordinary Syrians, which is why it's important that international governments push for agreements in the Geneva Syrian peace talks.
"But in the meantime, it is imperative that we invest in hope, education and livelihoods for the civilian population and pave the way for a more stable future."
Syria talks - Middle East blame game
Middle East newspapers apportion blame to a variety of sources for the suspension of the third round of peace talks in Geneva.
Ali Ibrahim Mattar in Iran's Arabic-language newspaper al-Vefagh says: "Saudi Arabia wants to make political solutions fail and sabotages any talks, in addition to its support for terrorist groups to destabilise Syria".
In Syria's state-run al-Thawrah daily, Ahmad Hamadah says: "The US secretary of state [John Kerry] and his aides flock to the Swiss capital… and behind closed doors impede all options for a solution."
Qatar's pro-government al-Rayah newspaper says: "Damascus, Moscow and pro-Syrian President Bashar al-Assad's sectarian militias made the Geneva talks fail from day one. These talks were stillborn."
Nasri al-Sayigh in the pan-Arab leftist Al-Safir daily bemoans the absence of the Syrians themselves - the refugees, displaced and missing - whilst the Saudi pro-government paper al-Watan says "Russian air strikes suspend Geneva 3 until 25 February".
The UN children's agency (Unicef) said on Tuesday that $1.4bn would be needed to rescue children in Syria and surrounding countries from becoming a "lost generation".
The vast majority of Syrian refugees are sheltering in neighbouring countries, including Turkey, Lebanon, and Jordan.
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Media captionJordan is facing pressure to help more refugees, despite the possible risk to its security
Jordan is hosting 635,000 of the 4.6 million Syrians registered as refugees with the UN. Speaking to the BBC ahead of Thursday's conference, Jordan's King Abdullah said his country was at "boiling point".
Thursday's conference is being jointly hosted by the UK, Germany, Norway, Kuwait and the UN.
UN Secretary General Ban Ki-moon called on those attending to "show unity of purpose in your political commitment towards Syria".
"I sincerely hope that this conference in London is used not only to mobilise funds but as a place where we can put strong pressure on the Syrian group and on the international community as a whole," he told the BBC.
More than 250,000 people have died in almost five years of war in Syria.
Eleven million others have fled their homes as forces loyal to President Bashar al-Assad and those opposed to his rule battle each other, as well as jihadist militants from so-called Islamic State (IS).
What is the Syria conflict?
Image copyrightAP
Why is there a war in Syria?
Anti-government protests developed into a civil war that, four years on, has ground to a stalemate, with the Assad government, the so-called Islamic State group, an array of Syrian rebels and Kurdish fighters all holding territory.
Who is fighting whom?
Government forces concentrated in Damascus and the centre and west of Syria are fighting the jihadists of Islamic State and al-Nusra Front, as well as less numerous so-called "moderate" rebel groups, who are strongest in the north and east. These groups are also battling each other.
How has the world reacted?
Iran, Russia and Lebanon's Hezbollah movement are propping up the Alawite-led Assad government, while Turkey, Saudi Arabia and Qatar back the more moderate Sunni-dominated opposition, along with the US, UK and France. Hezbollah and Iran are believed to have troops and officers on the ground, while a Western-led coalition and Russia are carrying out air strikes.
