While European leaders repeatedly said the measures were aimed at protecting migrants from the abuses of traffickers, they appeared at least as focused on shifting to African nations some of the burden of halting illegal migration.

This approach has similarities to that taken by the European Union in its 2016 deal with Turkey in which it agreed to pay Ankara some 6.6 billion euros ($7.9 billion) to keep migrants from crossing the Mediterranean, and help Turkey provide them with refugee camps. That agreement also permitted Greece to send back those who made it to its shores. The policy all but halted the flow of people taking the route through Turkey into Europe. In the first eight months of 2016, nearly 163,000 migrants crossed the Mediterranean entering through Greece. This year during the same period, just 14,000 came by the same route.

It is unclear if the proposals outlined Monday will require additional expenditures. Federica Mogherini, the European Union’s foreign affairs and security policy chief, who attended the meeting in Paris, said there was no need for “to invent a new Marshall Plan” for Africa since the European Union and individual European countries together already invest some 20 billion euros (about $24 billion) annually in African development aid and other programs.

Any European Union funds or programs might require the approval of other member countries.

Another spur for the policies agreed to Monday is the recent success that Italy has had in reducing the number of migrants arriving on its shores, said President Emmanuel Macron of France. He praised the Italian efforts to work with Libya’s coast guard. “What has been done by Italy and Libya is a perfect example of what we are aiming for,” Mr. Macron said.