March 22 (Reuters) - Canadian National Railway Co CNR.TO
* CN to purchase its common shares under a specific share repurchase program
* Canadian National Railway Co says purchase will form part of normal course issuer bid for up to 33 million shares (bid) announced on Oct. 25, 2016
* Canadian National Railway says will enter into an agreement with a third party to repurchase shares through daily purchases
* Says third party will purchase cn's common shares on open market in accordance with rules applicable to bid
* Canadian National Railway Co says agreement with third party to repurchase maximum of 1.8 million common shares
* Canadian National - price CN will pay for shares bought from third party to be negotiated by CN, third party; price will be at discount to prevailing market price Source text for Eikon: ID:nPn7BMrWfa Further company coverage: CNR.TO