Striking Canadian Pacific Railway workers could be back at their jobs by Friday afternoon, after legislation to force them back passed the Senate on Thursday evening and received royal assent.

In a release, the Teamsters Canada Rail Conference said it disagrees with the back-to-work legislation that will affect about 4,800 members of the union, but is advising its members to obey the law.

The House of Commons passed Bill C-39 early Wednesday morning after MPs sat all night Tuesday. Although it usually takes two days after introduction for the Senate to start debate, senators agreed to look at the bill Thursday.

CP workers walked off the job last Wednesday after talks over pension issues broke down.

Labour Minister Lisa Raitt said Wednesday that trains "have to start rolling again" 12 hours after royal assent for the back-to-work legislation.

Raitt appeared before the Senate committee of the whole on Thursday afternoon, along with CP management, union representatives and labour experts.