In a move many are calling politically motivated, the U.S. State Department delayed a decision on TransCanada Corp.’s Keystone XL pipeline to study alternative routes. The pipeline, planned to carry oil from Alberta, Canada through the heart of cattle country to Texas, has spurred a growing controversy between environmental groups and oil industry supporters.

The study of alternative routes could take 12 – 18 months, which would push the final decision on the pipeline until after President Barack Obama’s re-election bid in November 2012. In a release issued Thursday, the State Department said the study “could be completed as early as the first quarter of 2013.”

The delay is called a victory for environmentalists who oppose the pipeline and a setback for TransCanada Corp., whose $7 billion Keystone XL project is seen as the most important North American oil pipeline plan for decades.