German Chancellor Angela Merkel arrives in Greece on Tuesday to support its embattled government amid planned new anti-austerity protests, her first visit here since the economic crisis erupted more than two years ago. Thousands of police will create a safety zone for the visit of the German chancellor, a popular hate figure in the country who is often blamed for the harsh austerity measures imposed on Greece in return for vital international aid. Some 6,500 officers backed by water cannon and a helicopter have been mobilised for Merkel's six-hour visit, the first since the economic crisis made landfall in Greece in 2010. Left-wing newspapers urged Greeks to take part in protests planned in the capital but other media warned that any violence would be counter-productive. "Extreme actions, violence... can achieve nothing for the unemployed and pensioners and mainly undermine the country's position," said liberal daily Kathimerini. "Today's visit is critical and historic. Let us all handle it accordingly," the paper said. Merkel is due to meet with conservative Prime Minister Antonis Samaras and President Carolos Papoulias. She has faced criticism in Germany for failing to visit Athens since the economic crisis first erupted, unlike EU President Herman Van Rompuy, European Commission President Jose Manuel Barroso and eurozone chief Jean-Claude Juncker. In August, when Samaras visited Berlin, Merkel had insisted that she wanted the debt-wracked country to stay in the euro and pledged German help after crisis talks with the Greek prime minister. Merkel's office on Monday said she would convey a message of support for "ambitious" cuts already in place in Athens and encouragement to stay the course. "She is going to Greece to express her support for the ambitious reform efforts that the Greeks have set out and are -- in part -- beginning to implement," Steffen Seibert told a news conference. "We should not forget -- and I think this is sometimes forgotten in Germany -- that Greece can point to some successes when it comes to reducing the deficit through very difficult measures," added the spokesman. Samaras will greet Merkel at Athens airport at 1030 GMT and the two will then hold talks before holding a joint press conference. Merkel is then scheduled to see President Papoulias. "We believe this is a message of faith in the course of the Greek government, the Greek economy," government spokesman Simos Kedikoglou told Antenna television. "It is a positive step, it's important that the German chancellor is coming to Greece for the first time since the start of the crisis," he said. Leftist and Communist-affiliated unions are holding separate protests and a three-hour strike has been called in Athens from midday onwards. The police declared a ban on "public gatherings and demonstrations" in a broad section of the city centre that includes the German embassy, parliament and the offices of government but the union gatherings lie outside this area and will be held as planned. Merkel's route from the airport is also off-bounds. A front-page cartoon in top-selling Ta Nea daily showed Samaras sweeping protesters under a red carpet as Merkel's plane lands. "Syndicates and all of society will give a dynamic response to the plans of Merkel and European powers that are imposed by creditors and implemented by the government," the main Greek unions said in a statement. Merkel is widely reviled in Greece, where many blame the leader of Europe's paymaster Germany for imposing stiff austerity measures in return for vital international aid. In tabloid caricatures, she has even been depicted as Adolf Hitler and last month, during a general strike against spending cuts, protesters marching past the Bank of Greece crossed out "Greece" on the bank's sign and wrote "Merkel" over it. The visit comes at a crucial time for the heavily indebted country, which is in the midst of negotiations with its international creditors over a 13.5-billion-euro ($17.5 billion) package of cuts. A positive outcome is vital to unblock a 31.5-billion-euro installment from Greece's EU-IMF bailout package, which is needed to recapitalise banks and repay outstanding domestic debts in a country that is heading for a sixth straight year of recession.