MONTREAL, Que. — Tensions between between CN and striking members of the United Transportation Union escalated quickly today with CN locking out union members at various terminals in Canada where UTU members began staging rotating strikes last night.

“CN is a scheduled railroad, and we cannot run scheduled/precision freight operations without predictable manpower resources. Rotating withdrawals of employee services are very disruptive to the company. We must ensure the continuity of our operations,” said E. Hunter Harrison, CN president and chief executive officer.

The decision affects 280 workers for the duration of the conflict at terminals in Vancouver and Kamloops, B.C., and the Ontario municipalities of Brantford, Aldershot and Oakville, according to a Canadian Press report.

CN is attempting to keep its operations going across Canada with management personnel performing the duties of locked out UTU members.

The UTU formally requested that CN immediately resume collective bargaining and Harrison said CN is prepared to resume negotiations with the UTU. But no date for talks has been established.

The UTU launched renewed strike activity after announcing yesterday its members’ rejection of a tentative agreement with the company signed on Feb. 24, 2007. The tentative agreement, reached after a 15-day strike and finally voted on yesterday by union membership, was rejected by a vote of 1,553 opposed and 402 in favor. Thats about 79% of eligible votes cast rejecting the tentative agreement.

UTU members in Canada have been on strike at CN since Feb. 10, 2007, but suspended strike action and returned to work during the ratification process for the tentative settlement.

CN said the UTU has given the company verbal assurances that it will continue to protect commuter rail services in Toronto and Montreal during rotating labour action.