German Chancellor Angela Merkel is landing in Greece to show her solidarity with her Greek counterpart, prime minister Antonis Samaras, but economists are questioning what the visit will achieve, as the country faces a yawning budget deficit and a public debt that one former minister says is now not "repayable".
Seven thousand police officers have been scrambled to clear the streets of central Athens along with rooftop snipers and commandos to protect the German leader when she arrives in Athens at 13:30 local time (30 a.m. London time).
Greece's two largest unions threatened to defy a ban imposed on protesting in the city center, calling on their members to convene at Syntagma square. But CNBC's Carolin Roth reported that the police seemed to have things under control the streets were quiet on Tuesday morning.
But economists told CNBC that Merkel was the least of Greece's problems.
According to the latest economic forecasts from the International Monetary Fund (IMF), released on Tuesday, Greece will miss the five-year debt reduction target that underpins the country's 130 billion euro bailout.
The IMF forecast that Greek public debt will rise to 171 percent of gross domestic product (GDP) this year and 182 percent in 2013.
The IMF has also warned the Eurogroup of finance ministers who met in Luxembourg on Monday that Greece's debt would need restructuring and that it will be almost impossible to reduce the country's debt levels to a target of 120 per cent of economic output by 2020.
Jens Larsen, Chief European Economist at RBC Capital Markets, agreed that Greece's current debt situation was not sustainable.
"Greece will definitely have to do another restructuring," Larsen told CNBC's "Worldwide Exchange" on Tuesday.
"The question is how do they get one - as part of a deal or do they take one because there is no deal and things break down?"
Peter Doukas, Greece's former deputy minister of economy and finance and the current chairman at Capital Partner, told CNBC that Merkel's visit could not stave of the country's impending funding crisis and he said an official debt haircut was "absolutely inevitable."
"The Greek debt is not repayable at this point. The economy is too weak to afford a 300 billion euro ($387.9 billion) plus debt."
Greece is hoping to secure the next tranche of the 130 billion euros in aid from the troika. Without that aid, the country will run out of money by November, prime minister Samaras told a German paper. Doukas said that soon the subject of debt repayment would have to be re-addressed.
"Perhaps now isn't the best time to talk about it, but very soon we're going to have to talk about rescheduling of Greece's official debt. It simply isn't repayable."
That could prove hard because most of the debt owed to private creditors was reduced in the last restructuring, leaving mainly debt owed to the official sector: the European Union, the IMF and the ECB.
"There's going to be an official debt haircut or restructuring or rescheduling of sorts. My feeling is that it needs to go 15 years further in terms of maturity and a cutting of interest rates by at least 1.5 percent," Doukas said.
As personal incomes fall by 25 percent and youth unemployment increases to 55 percent, Doukas told CNBC, Greece faces its biggest hurdles yet and needed to pass reforms requested by the troika lenders (the IMF, ECB and European Commission).
"We are at the bottom of the pile...We need to balance our budget, reform our banking system...there are a lot of reforms that need to be taken...the more we delay, the more things get dragged on."
Doukas remained confident that the euro zone was firmly behind Greece and that Merkel's visit signified European solidarity with Greece. Citing Mario Draghi's announcement that the European Central Bank would support secondary markets in their sovereign bond-buying scheme, Doukas remarked that the euro zone was not willing to let Greece go, yet.
"It seems that Europe has determined that almost at any cost they will support the salvation of the euro and southern European countries."
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