MONTREAL -- Canadian National Railway (TSX:CNR) and the union representing about 3,000 employees have reached a tentative agreement to avert a Tuesday morning labour strike.

"CN is very pleased to have reached this settlement," said its chief operating officer Mike Cory in a statement.

A verbal agreement had been reached earlier in the day at about 4:15 p.m. ET, after talks resumed following an overnight round of bargaining and hours before the workers were in a legal strike position.

"It's always a good thing to avert a strike," said Stephane Lacroix of Teamsters Canada.

The union issued a 72-hour strike notice Saturday, which meant their workers would have been in a legal strike position early Tuesday morning.

Details of the agreement are being withheld pending ratification by union members, a process expected to take approximately 60 days.

Heading off a major rail strike is good news for the Canadian economy, said Bob Ballantyne, president of the Freight Management Association of Canada.

"I think all shippers that depend on CN will certainly be breathing a sigh of relief and I suspect the government will be breathing a sigh of relief as well," he said.

Ballantyne had warned that a strike would be damaging to the economies on both sides of the border and cause collateral damage to non-rail workers.

A full work stoppage would have caused plant closures in the $55-billion chemicals and plastics industry.

"In the case of a complete work stoppage, it would shutter most of our businesses within 48 hours maximum," Bob Masterson, CEO of the Chemistry Industry Association of Canada, said before a deal was reached.

Several large shippers had written to the federal government urging them to work to avoid a work stoppage or be prepared to order striking workers back to the table.