Poland's main opposition grouping has filed a proposal for a constitutional change that would make it possible for the country to leave the EU only with the backing of a two-thirds majority in parliament or through a referendum. Under the current rules, a simple majority vote in the lower house of parliament, along with the president's official notification to Brussels, is needed to take Poland out of the EU. Now the centrist Civic Coalition wants to make it harder for Polexit to take place.