Europe needs to come up with a plan now to get private investors to contribute to a bailout for Greece and give Athens time to deal with its problems, the head of the OECD club of industrialized nations said on Monday.

Time is critical, time is important to avoid a liquidity problem becoming a solvency problem. Time is of the essence also in order to allow for a recovery of everyone, Angel Gurria, head of the Organization for Economic Cooperation and Development, told reporters.

The euro zone's 17 finance ministers will discuss how to secure a contribution of private sector investors to the second bailout of Greece later on Monday.

Gurria, in Vienna for an economic survey of Austria, said it was essential for the private sector to take part in the Greek rescue effort.

Creditors should themselves contribute by extending the maturities (on debt) at least in the beginning, just extending the maturities long-term, allowing time for the policies to happen and then to be able to know better how much is required.

He said Greece needed time to carry out steps such as improved tax collection and its privatization plans.

Then in a few years time, if we have prolonged the time and given ourselves this space, this oxygen, we will be in a better position to determine whether some reduction in the nominal amount of the debt is necessary, he said.

(Reporting by Sylvia Westall; editing by Patrick Graham)