Venezuela-based oil and gas company PDVSA failed to make its interest payment on its 2024 and 2021 senior unsecured notes within the 30-calendar-day grace period, which expired on Dec. 16, 2017, and Dec. 17, 2017, respectively. In line with our criteria for timeliness of payments, we're lowering the issue ratings on these notes to 'D' from 'CC'. On Dec. 19, 2017, S&P Global Ratings lowered its issue-level ratings on Petroleos de Venezuela S.A.'s (PDVSA's) senior unsecured notes due 2024 and 2021 to 'D' from 'CC'. PDVSA hasn't been able to meet the coupon payment on its 2024 and 2021 notes within the 30-calendar-day grace period (or the bondholders hadn't received the funds by that date), constituting an event of default