Syrians have become the largest refugee population after Palestinians as at least three million people have fled Syria since the beginning of the civil war in 2011.
As per the UN's latest estimates, Syrians accounted for one in four of the 13 million refugees worldwide in 2014.
"As long as the international community continues to fail to find political solutions to existing conflicts and to prevent new ones from starting, we will continue to have to deal with the dramatic humanitarian consequences," UN high commissioner for refugees Antonio Guterres said in a statement.
The remarks were made a few weeks after Amnesty International warned that only five countries in the world host 98% of all Syrian refugees.
In its report, Left Out in the Cold, the NGO says that Iraq, Lebanon, Turkey, Jordan and Egypt have hosted 98% of Syrian refugees since the start of the crisis, while in the EU the number of refugees is 150,000.
Number of Syrian refugees in the five main host countries:
This figure is very similar to the number of people who reached Turkey fleeing the advance of terror group Islamic State (Isis) on Kobani in the space of one week in September 2014.
Sweden and Germany have received the majority of Syrian asylum applications in the last three years; 50,235 and 46,265 respectively.
The Syrian civil war has pitted President Bashar al-Assad supporters against rebels, causing the deaths of hundreds of thousands of civilians.
According to latest estimates, at least 191,000 people have been killed in the conflict while millions have fled their homes.
It is estimated that 6.5 million Syrians are internally displaced; of these, half are children.
According to UNRWA (United Nations Relief and Works Agency for Palestine refugees), there are some five million Palestinian refugees worldwide. Of these more than 1.5 million live in 58 Palestine refugee camps in Jordan, Lebanon, the Syrian Arab Republic, the Gaza Strip and the West Bank, including East Jerusalem.
Palestinian refugees are defined as "persons whose normal place of residence was Palestine during the period 1 June 1946 to 15 May 1948, and who lost both home and means of livelihood as a result of the 1948 conflict."
Afghans constituted the third largest refugee group, the UN said, with at least 2.6 million people hosted in camps in Pakistan and Iran.