Greece faces a Thursday deadline for a debt restructuring deal with private investors that is crucial to its new 130 billion euro ($172 billion) bailout package needed to avoid a chaotic default.

Athens said this week it aims for 90 percent acceptance but if the take-up is at least 75 percent then it would consider triggering so-called "collective action clauses" retroactively inserted into the bonds issued under Greek law.

A voluntary writedown "does not follow automatically, that is clear. But the Greeks have introduced this collective action clause. There is room here to get money from others who hold bonds which have been issued under Greek law," De Jager told parliament.

"About the private sector deal - I don't have a crystal ball. I cannot predict this with certainty. But, I repeat, for us this is a condition," he said, referring to a set of conditions which need to be met before the Netherlands can give final approval to the Greek bailout.

The Dutch parliament grudgingly gave conditional support for the bailout last month.

The Netherlands has been among the most reluctant countries to pledge support, with De Jager demanding close supervision of Greek budget cuts and reforms.

The finance minister stressed, however, the risks of not helping Greece.

"The risks are big, also for the tax payer, also when it concerns Greece. But not helping, not doing the program is a bigger risk for the euro zone," De Jager said.

Greece's bailout was about guaranteeing financial stability in Europe and probably the world, he said, referring to the market crisis in 2008 when U.S. bank Lehman Brothers went bankrupt.

"We have seen the consequences of a U.S. investment bank collapse in 2008, let alone what would happen if a number of banks went down in our own backyard, in southern Europe, in one or more countries because of contagion dangers, in our own monetary union. I estimate the risks to be much higher than with that bank's collapse."

De Jager reiterated he is in favor of raising the size of the euro zone rescue fund, European Stability Mechanism, and said he had asked in Brussels, where the European Union and its countries meet, whether Greece could get more help from other multilateral agencies.

"Can the EIB or EBRD play a role?," De Jager said,

The European Investment Bank (EIB) and the European Bank for Reconstruction and Development (EBRD) help finance investment projects in Europe.

(Reporting by Gilbert Kreijger; Editing by Toby Chopra)

Stocks treated in this article : Lehman Brothers Holdings Inc.