TransCanada is changing its plans for the construction of the Keystone XL pipeline, as approval for the project by U.S. President Obama is still pending. In an interview with Bloomberg Businessweek, the company's chief executive officer Russ Girling stated that the start of the project has been moved to 2016.

This is the second delay in the schedule for the high-profile oil pipeline this year but Girling said that TransCanada was realistic and was aware that there was no way for the project to commence in a period shorter than two years following approval. It is expected that a permit could be granted in early 2014 at the earliest, he said.

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Previously, TransCanada claimed that it was possible to build the northern section of the pipeline within a two-year period. The project has had to be revised several times, however, as the company was forced to shift the route of the pipeline to avoid land in Nebraska where ecosystems could be damaged by the project. Other revisions of the route have also been made.

At present, TransCanada is working on the southern section of Keystone XL. Since it does not cross the border no permit is needed for this leg, Bloomberg explained. However, the project has met with strong opposition from environmental groups and local communities, despite a draft analysis released earlier this year claiming that the pipeline is not likely to have a significant impact on harmful emissions.