The chief of the European Parliament called on Sunday for Britain to begin proceedings to leave the EU at a summit later this week, while Germany suggested the country should be given time to "reconsider."German Chancellor Angela Merkel sought on Saturday to temper pressure from Paris, Brussels and her own government to force Britain into negotiating a quick divorce from the EU, despite warnings that hesitation will let populism take hold.Merkel was set to host the leaders of France, Italy and the EU in Berlin on Monday amid fears Britain's vote to leave will create a domino effect in Eurosceptic member states.In what promises to be one of the bitterest summits in the history of the EU, British Prime Minister David Cameron will face huge pressure in Brussels on Tuesday to immediately trigger the two-year exit process.Britain's decision to leave the European Union puts Merkel at center stage, as the bloc seeks to preserve its unity and win back skeptical voters across the continent. Merkel has said there is "no reason to be nasty" regarding Britain's exit negotiations. She made clear she would not press Cameron after he indicated Britain would not seek formal exit negotiations until October at least.But some European leaders seem to be in conflict with Merkel, by expecting David Cameron himself to start the process in the coming days or weeks, officials said on Saturday. European Commission President Jean-Claude Juncker said it made no sense to wait until October to negotiate the terms of a "Brexit." He admitted that the EU had hoped Britain would stay, but that now it was key to make the separation process as quick and painless as possible.Foreign ministers of the six original EU members – Germany, France, Italy, the Netherlands, Belgium and Luxembourg – held an emergency meeting in Berlin to grapple with the first defection in the bloc's 60-year history. "We join together in saying that this process must begin as soon as possible so we don't end up in an extended limbo period," said Germany's Frank-Walter Steinmeier.European Parliament President Martin Schulz urged Cameron to begin the formal proceedings to leave and warned that failure to do so will risk jobs across the bloc. "Hesitating simply to accommodate the party tactics of the British Conservatives hurts everyone," Schulz told Bild am Sonntag. "That is why we expect the British government to now deliver. The summit on Tuesday is the right time."During talks in Berlin on Saturday the EU's six founding states urged Britain to leave "as soon as possible," now that it has made its choice, warning that the continent could not be left in limbo. Juncker also warned at the weekend that it would not be an "amicable" divorce.It will fall to Cameron's successor to lead the complex negotiations under Article 50 of the EU's Lisbon Treaty, which sets out a two-year timeframe to leave.