French Prime Minister Manuel Valls has warned that Europe's migration crisis is putting the EU at grave risk.
Mr Valls told the BBC Europe could not take all the refugees fleeing what he called terrible wars in Iraq or Syria.
"Otherwise," he said, "our societies will be totally destabilised."
More than a million migrants, mostly refugees, arrived in Europe last year, many making perilous journeys. On Friday, at least 21 people were killed as their boats sank off Greek islands.
Mr Valls also said that France would seek to keep its current state of emergency until a "total and global war" against so-called Islamic State (IS) was over.
The measures were introduced after the IS-led Paris attacks on 13 November and then extended for three months.