The companies say they now expect the transaction to close on Jan. 29, 2021.
Bombardier has been working to transform itself from a maker of trains and aircraft into a company focused on business jets.
Alstom shareholders voted to approve the deal on Oct. 29.
The sale is expected to make Alstom the second-largest manufacturer of rolling stock, behind China’s CRRC.
Alstom has committed to establish its North American headquarters in Montreal, which will oversee 13,000 employees, set up a research centre and improve production at the Bombardier Transport plant in La Pocatiere, where the order book is almost empty.
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