VEB did not respond to an emailed list of questions.
Activists who oppose the project also say that by approving it the Ex-Im Bank would risk violating an O.E.C.D. convention designed to prevent export credit agencies from forming a partnership with corrupt foreign officials. On Monday, Dinh La Thang, PetroVietnam’s former chairman, was sentenced to 13 years in prison for economic mismanagement, in an anticorruption push that experts widely regard as more a reflection of political infighting than a desire to eliminate graft in Vietnam, a one-party state.
Mat Tromme, a senior research fellow at the Bingham Center for the Rule of Law in London who previously worked on anticorruption projects in Vietnam, said that proving a violation of the O.E.C.D. convention could be difficult because its definition of corruption can be vague.
But he said that it was “relatively easy” to see how the case could fall within the convention’s provisions, and that the Ex-Im Bank might feel pressure from export credit agencies in countries like Britain, Canada and Germany that have what he called “tough” positions against bribery and corruption.
PetroVietnam officials did not respond to multiple requests for comment. The Ex-Im Bank said it would consider any evidence of mismanagement.
Work on the project is already underway. On a recent weekday, welding sparks could be seen inside the skeleton of the plant, which is about the size of an office building.
Le Thi Tam, who lives nearby, said that officials had paid her about $2,400 to relinquish her farmland on what is now the project site. Pollution from the plant is a concern, Ms. Tam said, but that is hardly worth complaining about.
“It’s government policy,” she said. “Who can argue with that?”