CHICAGO | A federal appeals court in Washington ruled Monday that the U.S. Surface Transportation Board doesn't have to issue a decision by Dec. 1 on a request by Canadian National Railway to purchase the Elgin, Joliet & Eastern Railway Co.

When filing its case with the court in August, Canadian National claimed it needed approval by the end of the year if it was to close the deal with U.S. Steel, which owns the EJ&E Railway.

It told the court its stock purchase agreement with U.S. Steel terminates Dec. 3 and that the steel company was unwilling to extend the deal.

A week later, it asked the Federal Surface Transportation Board to issue a final decision on the economic merits of the purchase by Oct. 15.

CN didn't immediately comment on the appeals court ruling.

The Surface Transportation Board has subjected the deal to a vigorous environmental review, which is not expected to be completed until next year.

The Montreal-based railroad told the board it would maintain the environmental "status quo" on the EJ&E line until the environmental review was completed.

A draft environmental impact statement issued by the board's Section of Environmental Analysis earlier this year concluded the railroad will need to enhance safety at 15 EJ&E rail crossings and take other actions to lessen the impact of increased train traffic.

Train traffic through Gary, Griffith, Schererville and Dyer would increase three-fold under the deal. Train traffic through Munster and Lansing would be drastically cut.

The court wrote that a quick decision is only necessary in "extraordinary situations," and Canadian National's request doesn't qualify.

The Associated Press contributed to this story.