The European Union lashed out at member countries for failing to come up with funds to help cope with the refugee emergency.
The European Commission complained that only three of 28 nations have pledged a total of just €12m to a fund to help African nations better manage their borders.
The pot is meant to total €1.8bn over two years.
The EU’s border agency and asylum office have appealed for a total of around 1,000 officers to help fingerprint people and decide whether they are eligible for asylum.
So far, about a dozen of the 28 EU nations have offered around 130 personnel.
“Words need to be matched with action,” European Commission Vice President Frans Timmermans told reporters, in a message timed to reach the heads of state and government ahead of a summit in Brussels.
More than 500,000 people fleeing war or poverty have entered Europe this year, most of them via Greece and Italy, overwhelming border authorities and reception facilities.
Under the media spotlight, EU leaders pledged last month to provide hundreds of millions of euros in aid for Syrian refugees and to tackle the problem at its roots, in Africa and Turkey.
In an effort to spur countries into action, the European Commission last month also sent 40 warning letters to members over their failure to properly implement EU asylum laws and procedures. None have replied.
At their summit, the fourth this year focused on the migration challenge, the leaders will debate ways to strengthen Europe’s borders to the outside world, including a possible EU border guard.
They will discuss whether to abandon the rules that require people to apply for asylum in the first EU country of arrival, a system that is a cornerstone of EU policy but which has virtually collapsed under migrant pressures this year.
The leaders will also examine Turkey’s request for a safe zone in northern Syria, from where most migrants are leaving.
Almost two million Syrian refugees are living in Turkey, and hundreds of thousands have already left there this year to cross into Greece.
While the EU desperately needs Ankara’s cooperation to ease the migrant flow, there is very little that Europe can do in Syria itself.
“Creating a solution which is direly needed for Syria will happen at the UN level, in the Security Council, or it will probably not happen,” Mr Timmermans said.
The summit chairman, EU Council President Donald Tusk, warned the leaders not to be lulled into thinking the migrant challenge will ease as winter approaches.
“We must be ready for spring and the threat of bigger waves flowing into Europe,” he wrote in his invitation letter to the leaders.
“We must ask ourselves if the decisions we have taken so far, and the ones we are going to take on Thursday, are sufficient.”