Netherlands-based mail and logistics solutions operator PostNL reported weaker-than-expected operating cash flow, which led to lower cash accumulation, higher adjusted debt, and credit measures falling short of our rating guideline in 2018. Despite limited prospects for debt reduction in the medium term, PostNL will likely improve its credit measures to a level consistent with the current 'BBB+' rating. This will take longer than we previously expected and hinge on the company's ability to gradually recover its operating cash flows, while maintaining its stated dividend distribution thresholds. We are therefore affirming our 'BBB+' long-term and our 'A-2' short-term ratings on PostNL. The negative outlook indicates that we may lower the ratings over the next 12-24 months if PostNL fails to restore