-- PDVSA's liquidity tightened due to the decline in oil prices at the end of 2008 and continued tax payments to the government. -- In our opinion, there is heightened uncertainty regarding the company's willingness to meet its contractual obligations with some of its suppliers. -- We are lowering our rating on PDVSA to 'B+' from 'BB-'. -- The negative outlook reflects what we believe to be heightened uncertainty regarding PDVSA's liquidity and its willingness to meet its obligations with suppliers, as well as the negative outlook on Venezuela. MEXICO CITY (Standard&Poor's) June 12, 2009--Standard&Poor's Ratings Services lowered its long-term corporate credit rating on Petroleos de Venezuela S.A. (PDVSA) to 'B+' from 'BB-'. The outlook remains