The proposals would make it possible for British lawmakers to work with European counterparts to block unwanted EU laws and also recognize that Britain faces an "exceptional situation" regarding the influx of immigrants taxing Britain's social services. Cameron, who needs to convince skeptical members of his own Conservative Party that staying in the EU serves Britain's needs, si seeking concessions ahead of a planned referendum on whether Britain should remain part of the EU. On the contentious issue of benefits for EU migrant workers, Tusk says that EU treaties must be respected, but he suggests there is room for maneuver by saying that current rules on the free movement of people could be clarified. [...] Cameron's push to hold a referendum has raised troubling questions about the future of the European project at a time when a refugee emergency and economic crisis in Greece weighs heavily on the bloc.