Venezuela has reached negotiated agreements after taking over the operations of other companies such as Swiss cement maker Holcim and Mexican cement company Cemex SAB.
Decisions in the arbitration cases could put major financial pressures on Venezuela at a time when Chavez is running for re-election and has been increasing government spending.
"Why do we have to go there, to the United States?" Chavez said of the ICSID. "The World Bank, what's that?"
Chavez had mentioned previously that the government was considering abandoning the arbitration body, following the leftist governments in Ecuador and Bolivia, which have pulled out in the past several years. But analysts had described a Venezuelan pullout as unlikely because it would likely bring various financial consequences for the government, including affecting its government bonds.
"Tomorrow, I'm sure that bonds are going to fall," said Asdrubal Oliveros, an economist and director of Ecoanalitica. "This is going to generate a lot of noise."
Regardless of what Chavez says, Venezuela "has an obligation to accept the decisions that the ICSID is going to make with respect to Conoco and Exxon," Oliveros said in a telephone interview. He said the government already accepted the arbiter in all of the pending cases and cannot take that back.
If the government eventually goes through with Chavez's idea, companies will be able to go after Venezuelan assets in the U.S. and elsewhere, Oliveros said.
He noted, however, that several years ago Chavez similarly vowed to pull out of the International Monetary Fund but found it impractical.
"I think that when they realize the impact of pulling out of the ICSID... the government will probably reverse course," Oliveros said.
Michael Nolan, a Washington lawyer who represents clients considering arbitration suits against Chavez's government, agreed that a withdrawal by Venezuela should not have any effect on cases that are already under way. He said companies should still also be able to file new arbitration cases for some time because there is a six-month "sunset provision" in a key convention to which Venezuela is a party.