The Greek exit will not be risk free for the eurozone, but it shall not endanger the stability of eurozone as a whole nor bring down the single-currency bloc, a senior Germany economist said.

In an exclusive interview with Xinhua, Joerg Kraemer, chief economist with the Commerz Bank said he disagreed with some analysts that a possible Greek exit from the eurozone could lead to the collapse of the currency shared by 17 countries.

According to Kraemer, private creditors have already lost the bulk of the money they invested in Greece in a debt swap deal with the Greek government several months ago. In addition, discussions about a possible Greek exit has been going on for quite a while, leaving enough time for everybody to prepare for it, he said.

"These are the two main reasons why I think that Greece no longer has the potential to threaten the stability of the eurozone as a whole, or that Greece no longer has the potential to cause the current eurozone to collapse," Kraemer said.

The ECB last week stop accepting Greek sovereign bonds as collateral in eurosystem monetary policy operations. An ECB statement said the governing council would assess the potential eligibility of Greek government bonds following the conclusion of the currently ongoing review of Troika of the progress made by Greece under the second adjustment program.

The move taken by the ECB has raised the concern of some analysts who believed Greece could probably default and leave the eurozone once the Troika, including European Commission, European Central Bank and International Monetary Fund cut off the bailout loan.

"In the medium term the Troika is likely to come to a negative conclusion which is anyway overdue," said Kraemer.

According to Kraemer, this means the EU and the IMF will pull the plug for Greece, stop sending Greece fresh money.

Such a move could lead to an outright default of the Greek government and would cause a period of economic chaos, during which the Greek government is likely to decide to leave the Euro zone, according to Kraemer.

In this scenario they are likely to reintroduce Drachma, the currency Greece used before it joined the eurozone in 2001, to work out of the mess with depreciation, which would make Greece more competitive for manufactured goods, Kraemer said.

Meanwhile, Kraemer pointed out that "the reason for the sovereign debt crisis is that the periphery countries, did not implement the setup which is consistent with the monetary union."

Italy allowed its productivity to stagnate and wages to increase without being covered by productivity increases, while Spain and Ireland allowed a huge real estate bubble to develop, he said.

He proposed to set up a European fiscal supervisory authority in the eurozone. As an independent institution like the ECB, the European fiscal supervisory authority would define a maximum budget deficit for eurozone countries.

"The higher debt to GDP ratio, the lower the deficit should be," he said.

Kraemer envisioned that the institution should also be responsible for the issuance of debt in the name of these countries "simply to make sure that these countries do not borrow at will."

"I think such a transfer of national sovereignty is justified because it still leaves open to the countries to decide by their own which combination of taxes and spending they would like to have," said Kraemer.

Kraemer considered the bond-buying and three-year Longer-Term Refinancing Operations conducted by the ECB as "an indirect form of state financing, which is banned by the EU treaty."

"Financing states is not the job of ECB. That's the job of the finance ministers of the eurozone and they should do this job," he said.