As many as 78 nations and 40 international organisations will attend the third donors conference aimed at raising billions of dollars for war-torn Syria, host country Kuwait said Monday.
The March 31 gathering at foreign ministers level will be opened by Emir Sheikh Sabah al-Ahmad Al-Sabah and UN Secretary General Ban Ki-moon, a foreign ministry official told the KUNA news agency.
Nations are expected to announce pledges for UN humanitarian operations in Syria where 12 million people both inside and outside the country need urgent aid.
At the first and second conferences, also hosted by Kuwait, pledges of $1.5 billion and $2.4 billion were made, but the United Nations has complained that not all pledges were honoured.
Ahead of the conference, international non-governmental organisations are due to meet to make their own pledges.
Ban urged the Security Council on Thursday to overcome divisions and take action to end the war in Syria as the conflict entered its fifth year with little prospect for peace.
His appeal followed scathing criticism from 21 human rights and aid groups who accused world powers of "failing Syria" in a report that highlighted the worsening plight of civilians.
Last year was the war's deadliest yet, with at least 76,000 people killed out of a toll of more than 215,000 since it erupted on March 15, 2011 with peaceful demonstrations inspired by the Arab Spring in Tunisia.
Around four million Syrians have fled abroad and 7.6 million are displaced inside the country as Assad's forces battle opposition rebels and extremists from the Islamic State group.