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BERLIN, April 16 (Reuters) - Germany's foreign minister said on Sunday it was good that the acrimonious Turkish referendum campaign was over and urged people to stay calm with the 'Yes' vote for constitutional change to expand President Tayyip Erdogan's power narrowly ahead.
President Tayyip Erdogan celebrated what he said was a clear result but opponents said they would challenge the vote count, which gave a narrow 51.3 percent lead to Erdogan's supporters. The head of the Turkish electoral board said the 'Yes' vote won .
"We'd be well advised to keep calm and to proceed in a level-headed way," Foreign Minister Sigmar Gabriel said in a statement.
"It's good that election campaign, which was fought so bitterly, including here in Germany, is now over," said Gabriel, a member of the Social Democrats (SPD) - the junior partner in Chancellor Angela Merkel's ruling coalition.
During the campaign, Erdogan repeatedly attacked European countries, including Germany and the Netherlands, accusing them of "Nazi-like" tactics for banning his ministers from speaking to rallies of Turkish voters abroad.
Peter Altmaier, Merkel's chief of staff, said on German broadcaster ARD that the result showed there was a "very lively political debate" in Turkey, but it was necessary to wait for official results before commenting further.
He said there were election observers in Turkey and the German government "would of course respect a result that came about in a free and democratic vote".
Asked if the vote was free and democratic, Altmaier said the German government would discuss the result once it was official and election observers would look at whether it was fairly conducted.
Manfred Weber, the German leader of the conservative bloc in the European Parliament, told German broadcaster ZDF that Turkey was heading in the wrong direction, pointing to mass dismissals in the wake of July's failed coup and the jailing of journalists and civil servants.
"Now that Turkey has obviously taken the wrong path from a European perspective, we need to re-evaluate our relationship, and specifically that means that the EU accession talks with Turkey that we're still having can no longer be continued."
Germany has about three million residents of Turkish background, about 1.41 million of whom are Turkish citizens who were eligible to vote in the referendum.
Senior SPD member Axel Schaefer said majorities reached in democratic votes could turn against democracy itself, pointing to the 1933 elections in Germany, when support for Adolf Hitler's Nazis surged.
"The Brexit vote is pushing Britain into the sidelines, the presidential election of (U.S. President Donald) Trump is taking the USA on an adventure, the Erdogan referendum is leading Turkey into absolutism and the 1933 German parliamentary election led Germany into the abyss," he said.
Cem Ozdemir, a leader of Germany's opposition Greens who is of ethnic Turkish origin, said on Twitter it was a "black day for Turkey" but added: "Almost 50 percent voted for democracy and against dictatorship. We stand by their side."
Beatrix von Storch, a member of the European Parliament for Germany's anti-immigrant Alternative for Germany (AfD) party said on Twitter: "All Turks with a German passport who today voted in favour of an Islamic dictatorship in Turkey are very welcome to leave Germany." (Reporting by Michelle Martin; Editing by Robin Pomeroy, Larry King)