Europe must be careful not to turn itself into a fortress just to keep out immigrants, a French minister has said.
Thousands of Africans are risking their lives to reach Europe
Addressing a European-African migration conference, French Interior Minister Nicolas Sarkozy said the concept of zero immigration was a dangerous myth.
Ministers from 57 European and African nations are meeting in the Moroccan capital Rabat to discuss ways of dealing with migrants.
Increasing numbers of Africans are coming to Europe in search of work.
Delegates are discussing human trafficking and security but also ways of alleviating the poverty which causes many migrants to seek a better life.
Already this year at least 8,000 African migrants have reached Spain's Canary Islands alone.
Hundreds more have landed on Malta and the Italian island of Lampedusa.
Speaking at the opening of the two-day conference, Mr Sarkozy, who is known for his hardline view on immigration, warned that it would not be in Europe's interest to turn itself into a fortress.
But he warned that Europe could not absorb all those who saw it as an El Dorado - a move which, he said, would destabilise the continent.
The failure to offer opportunities to African youth today would spell disaster for Europe tomorrow, he warned.
Mr Sarkozy, who has been widely attacked for drafting a controversial new law to curb immigration to France, also called for a new financial institution to help African migrants in Europe to send money home.
Delegates also heard a statement from French President Jacques Chirac in which he called for a joint approach to tackle illegal immigration "with respect for human dignity but with firmness".
Illegal migration required an "energetic fight against trafficking networks" along with "co-operation to improve border surveillance," he said, while stressing the need for Europe to enter a development partnership with Africa.
"Let us offer Africa's youth a future of dignity. Then it will not risk resorting to violence and extremism, or choosing, en masse, the paths of exile," he said.
The Rabat conference is supposed to develop a common approach between Europe and Africa - tougher policing and action against human trafficking but also measures to deal with the poverty and conflict which drive would-be migrants to seek a better life elsewhere.
The UN High Commissioner for Refugees Antonio Guterres said that the movement of both refugees and migrants was frequently rooted in the broader problem of under-development.
Presenting delegates with a 10-point action plan, Mr Guterres urged governments to work together to protect the rights of both refugees and migrants.
"I hope that this conference will enable the states of Africa and Europe to formulate cooperative approaches to the challenge of development - approaches which can help us to create the conditions that enable people to migrate out of choice, rather than necessity," he said.
Europe talks increasingly about managed migration, choosing the migrants it wants to fill gaps in the labour market.
But African countries fear that means they will lose their best and brightest, slowing down their development still further.
Morocco is the jumping-off point for migrants from sub-Saharan Africa, from Senegal and Mali, Cameroon and the Democratic Republic of Congo.
But many get to Morocco only to find they cannot go any further - the land routes are closed and there are more patrols at sea.
The Moroccan authorities do not want them there.
They have stopped granting residence permits even to statutory refugees.
Many of the migrants complain of racism and violence.
They stay because going back would be worse - for some because their countries are at war, for others because the shame of admitting defeat is simply too great to be borne.