Ahead of a summit of eurozone leaders on Thursday, European officials laid out three options for securing private-sector involvement in another financial aid package for Greece. Dutch and German parliamentarians have demanded that banks contribute to averting a Greek default.

The single currency bloc is urgently attempting to secure enough financing for Athens for the next three years and put and end to market concern about the sustainability of public debt in other Southern European economies, including Italy and Spain.

The first option, as reported by Reuters, would involve buying back Greek debt which could trigger further credit downgrades if not default. Under this scenario, the country would replace existing debt obligations with new bonds in a swap operation backed by more creditworthy European partners.

The second option is based on a French proposal for a debt rollover which would probably also cause a selective default.

The third and only option to avert bankruptcy would be to impose a tax on the financial sector or convince Greek banks to maintain their currently high levels of exposure. This would be the cheapest option for European governments but riskiest for private lenders.

The Greek state is more than €340 billion in debt. With a population of over eleven million, that amounts to some €30,000 per person or 150 percent of annual economic output. €110 billion worth of financial aid from fellow European nations and the International Monetary Fund last year has proven insufficient so a second package worth up to €120 billion is under discussion.

If Greece defaults, it could prompt more bailouts — for Greece, presumably from the International Monetary Fund, because it would be cut off from financial markets but also for European, particularly German banks that have invested billions in Greek bonds.