It follows a week that saw hundreds more people drown in the Mediterranean and 71 die in a lorry in Austria. A record number of 107,500 migrants reached the EU's borders last month.

The UN says the continuing conflict in Syria is a major factor behind the rise in numbers. Border controls in Greece, Italy and Hungary have particularly struggled with the stem of migrants from not only Syria but the rest of the Middle East and Africa.

Next month's extraordinary meeting was announced by late on Sunday Luxembourg, which holds the EU's rotating presidency.

"The situation of migration phenomena outside and inside the European Union has recently taken unprecedented proportions," it said in a statement.

In July, the number of migrants that reached the EU's borders topped 100,000 for the first time - triple the number of people in July last year, according to European agency Frontex.

Discussion points will include internal co-operation, fighting the trafficking of migrants, and return policy. Germany, France and the UK have said the EU should establish a list of "safe countries of origin" that would allow immediate repatriation of some migrants.

On Saturday Secretary-General Ban Ki-moon said much more was required to prevent the deaths of people fleeing to Europe and called for a "collective political response". He said he was "horrified and heartbroken" by the discovery of 71 dead people - believed to have fled the Syrian conflict - in a lorry in Austria on Thursday.

At least 2,500 migrants have died since January, most of them drowning in the Mediterranean.