Venezuela is prepared to invest sufficiently to assure the opening of a jointly operated oil refinery in Brazil within the foreseen timetable, Venezuelan President Hugo Chavez said Tuesday.

Speaking to reporters following a ceremony marking the acceptance of Venuezuela into the Mercosur customs union, Mr. Chavez said his government expected the Abreu e Lima refinery in Brazil's northeastern state of Pernambuco to begin operations in 2014 at a production capacity of 230,000 barrels per day.

"We're resolving some problems, but there's no doubt the refinery continues as planned," the president said.

The refinery effort was launched during the government of former Brazilian President Luiz Inacio Lula da Silva, but has suffered delays amid difficulties by Venezuela's state-oil company Petroleos de Venezuela SA, or PdVSA, to assure financing for its portion of the project. The company has been given until November to come up with loan guarantees for the project for Brazil's BNDES National Development Bank.

Mr. Chavez said the entrance of Venezuela into Mercosur would facilitate projects such as the refinery as well as trade throughout the region.

"The entrance of Venezuela represents a leap forward for Mercosur," he said. "No doubt it will strengthen the entire market."

Speaking earlier in the afternoon, Brazilian Trade Minister Fernando Pimentel said Brazil's government planned to send a delegation to Venezuela at the end of August to negotiate increased trade of oil and other products.

"Venezuela offers many products that could be important for the Brazilian industrial chain and Brazil also has many products to offer Venezuela," Mr. Pimentel said. "It's going to take some time before Venezuela is completely integrated into Mercosur but we're going to work so that trade between the countries increases quickly."

In addition to increased oil trade, Brazilian and Venezuelan officials said they were interested in discussing increased commerce in other areas such as automobiles and agricultural goods.

Write to Gerald Jeffris at gerald.jeffris@dowjones.com