(Updates with latest events)

Aug 23 (Reuters) - Workers at Canadian National Railway ( CNI )

will begin to return to work on Friday, a major labor

union said, after the Canadian government moved in to end an

unprecedented rail stoppage.

Rival Canadian Pacific Kansas City ( CP ) is also

preparing to restart operations and is awaiting an order from

the Canadian Industrial Relations Board (CIRB).

CN and CPKC locked out more than 9,000 unionized workers on

Thursday after contract talks with the Teamsters union were

deadlocked.

Here is a timeline on the negotiations between the parties:

Date Events

Dec. 31, Contracts covering locomotive engineers,

2023 conductors and yard workers at CN and CPKC

expire.

Feb. 19, Teamsters claim that CN and CPKC are "not

2024 serious about negotiating and avoiding a work

stoppage".

May 1, 2024 9,300 railway workers at both companies vote

to strike as early as May 22.

May 10, The Canadian government says it is moving to

2024 push back the start of a possible strike by

railway workers.

May 16, CPKC says its leadership, with the assistance

2024 of federal mediators, will resume negotiations

meeting with Teamsters on May 17.

May 23, CPKC says talks have hit a deadlock,

2024 predicting that a legal strike or a lockout

would not likely occur before mid-July.

June 7, The union says CN and CPKC rejected a proposal

2024 to stagger negotiations with both companies by

two weeks.

Aug. 5, The companies and union restart negotiations

2024 along with federal mediators, says Minister of

Labor Steven MacKinnon.

Aug. 9, Teamsters warns a work stoppage could start on

2024 Aug. 22 if a deal is not reached.

Aug. 9, The rail companies say they would lock out

2024 employees on Aug. 22 if talks to negotiate a

labor contract fail.

Aug. 15, Minister Steven MacKinnon rejects a request by

2024 CN Rail to initiate binding arbitration.

Aug. 17, CPKC says will halt any new rail shipments

2024 originating in Canada, and all new U.S.

shipments destined for Canada starting on Aug.

20 if talks fail to progress.

Aug. 18, The railroad operators issue lockout notices

2024 to workers represented by the Teamsters union.

Aug. 19, Labor minister says he will meet with both

2024 companies and the union in Montreal to avert

stoppage.

Aug. 22, CN and CPKC shut down their rail networks in

2024 the country and lock out nearly 10,000

workers.

Aug. 22, Canadian government explores all the ways it

2024 could use the country's labor code to end a

nationwide rail stoppage, including binding

arbitration.

Aug. 23, Teamsters says workers at CN will return to

2024 work on Friday.

(Reporting by Aishwarya Jain in Bengaluru; Editing by Sriraj

Kalluvila)