Euro Still Vulnerable to Greek Debt Drama

NEW YORK—Greece’s efforts to reduce its crushing debt load will take center stage this week, with still-cautious investors likely to sell the euro if negotiations falter.

Ahead of a coming March 20 bond-redemption deadline, Athens must persuade at least 90% of its private bondholders by Friday to participate in a voluntary debt exchange. As part of a recent €130 billion ($172 billion) assistance package, investors are being asked to accept a 53.5% write-down on their holdings, which will help keep the Hellenic republic from spiraling into a destabilizing default.