The Obama administration plans to move a key decision on whether to approve the massive Keystone XL tar sands pipeline until after the 2012 presidential election, according to reports late Thursday that cited administration insiders.

While an official announcement was expected sometime this week, administration sources told USA Today and The New York Times that a decision would not be made before the election, and that the pipeline's route may ultimately be changed.

The revelation comes just days after the Office of Inspector General (OIG) announced it would investigate how the State Dept. handled the deal with TransCanada to secure the pipeline's route.

The investigation would likely look at emails released earlier this year by environmental advocacy group Friends of the Earth, which claimed that documents obtained through Freedom of Information Act (FOIA) requests showed improper relationships between TransCanada lobbyists and State Dept. employees. Officials have since denied “complicity” in helping to secure the deal, which the State Dept. claimed would have minimal environmental impact.

Environmentalists disagree with this position, pointing to spill after spill of toxic crude oil. One striking example often cited by activists was the rupture of an Exxon Mobile pipeline earlier this year, which contaminated Yellowstone River. That pipeline was carrying crude oil from tar sands, which is known to be heavier and even more toxic than other types of oil.