European Council President Donald Tusk issued a stark warning on Tuesday that the European Union had "no more than two months" to tackle the migration crisis engulfing the 28-nation bloc or else face the collapse of its passport-free Schengen zone.Tusk was speaking to the European Parliament in Strasbourg amid growing frustration in Brussels and Germany - the bloc's biggest economy and main destination for migrants arriving in Europe - that the EU seems unable to get its act together on its worst migration crisis since World War Two."We have no more than two months to get things under control," Tusk, who chairs the summits of EU leaders, said."The March European Council (summit) will be the last moment to see if our strategy works. If it doesn't, we will face grave consequences such as the collapse of Schengen."The European Council summit on March 17-18 will focus mainly on the migrant crisis. The Schengen system has already been suspended in some countries like Denmark, Germany and Sweden, which have introduced controls at their borders in order to stem the flow of migrant and refugee arrivals.Tusk said that EU governments have failed to deliver on commitments to curb the flow of refugees and migrants reaching Europe, with more than 1 million arrivals last year and figures showing little sign of decreasing over the winter months.A landmark deal with Turkey, which is meant to keep more people on its soil in exchange for funding for migrants and reviving its long-stalled EU membership talks, "was still to bear fruit", Tusk said.On creating the bloc's joint border guard - another measure to address the migration crisis - Tusk said he expected a political agreement between EU leaders when they meet for a summit in June.He said the EU would "fail as a political project" if it could not control its external borders properly.The crisis has exposed bitter disputes among EU countries, with some blaming Greece and Italy for letting too many people in. Athens and Rome say Germany's initial open-door policy encouraged more arrivals than anyone could cope with.DEAL WITH BRITAINTusk also said he would present his detailed proposal on talks with Britain ahead of a summit next month over its demands for changes to the bloc that London says are necessary for the country to stay in.The most contentious demand is to allow London to curb benefit payments to EU migrants for four years after they arrive in Britain."There will be no compromise on fundamental values on non-discrimination and free movement," Tusk said. "At the same time, I will do everything in my power to find a satisfactory solution also for the British side."He said time he would try to obtain a deal in February.