Republican presidential candidate Rudy Giuliani on Sunday defended his law firm’s role in representing Citgo Petroleum Corp., which is ultimately controlled by Venezuelan President Hugo Chavez, saying it was helping to protect American jobs.

Giuliani acknowledged, though, that his opponents will try to exploit news this week that a lawyer with Bracewell & Giuliani, of Houston, has been representing Citgo before the Texas Legislature. The firm has had a contract with Citgo since before Giuliani joined it.