The European Union faces a first test in its attempt to turn the page on the two-year debt crisis when Greece's private creditors decide this week whether to sign off on the biggest sovereign-debt restructuring in history.

The success of the 106 billion-euro ($140 billion) debt swap, confirmed on the eve of last week's European Union summit, depends on how many investors agree to the writedown by the March 8 deadline. Euro-area finance ministers will hold a teleconference on March 9 to review the deal's outcome.

"The European crisis is not quite over yet," Erik Nielsen, chief global economist at UniCredit SpA in London, wrote in a note to clients yesterday. He said enough creditors will probably participate in the writedown to avoid triggering so-called collective action clauses, which could be used by Greece to compel investors to participate and roil markets by triggering credit-default swap insurance contracts.