A top official from oil giant Shell told the then-US ambassador in Abuja that the firm had "access to everything that was being done" in key Nigerian ministries, a leaked diplomatic cable showed on Thursday.
The US diplomatic cable, published by Britain's Guardian newspaper and part of the huge trove of documents released by WikiLeaks, was dated October 20, 2009.
It said Ann Pickard, then Shell's executive vice president for sub-Saharan Africa, had met with the US ambassador at the time, Robin Renee Sanders, and discussed a range of issues.
Pickard commented on Shell's inside government information after discussing China's reported interest in Nigerian oil blocks, the cable said.
"She said the (government of Nigeria) had forgotten that Shell had seconded people to all the relevant ministries and that Shell consequently had access to everything that was being done in those ministries," the cable said.
Shell, which declined comment, is among the major oil producers in Nigeria, which is an OPEC member and one of the world's largest oil exporters.
The US embassy also refused comment, while Nigerian government officials could not immediately be reached.