GO Transit trains in the Greater Toronto Area are operating on schedule Monday despite a strike by CN conductors, who walked off the job across Canada on Saturday.

As had been promised by both CN management and the union since the weekend, service for the 165,000 daily GO commuters was not interrupted by the work stoppage.

CN's 2,800 conductors and yard-service workers walked off the job early Saturday, but a deal between CN and the United Transportation Union last week ensures that GO Transit would keep running in the event of a strike.

The deal states the union must give at least 72 hours notice for the cancellation of any commuter trains.

Meanwhile, a hearing to determine the legality of the will be held in Montreal on Tuesday by the Canada Industrial Relations Board.

Union officials in Canada believe the strike is legitimate because, according to the Canadian labour code, employees were in a legal strike position.

But officials in the U.S. had different interpretation, saying the strike was "unauthorized" by the international union president.

CN management, who is suing the union for damages over the work stoppage, is filling in for the conductors. The strike has had "minimal" impact so far, said spokesman Mark Hallman.

Workers are on strike for a number of reasons, including "harassment and intimidation" by management, longer lunch breaks and changes to the company pension plan, said the union's chief negotiator Rex Beatty.

Hallman, however, told CTV Newsnet on Monday that one of the main issues is the UTU's demand for "excessive wage increases."

"The UTU's final offer on wages -- three years at 4.5 per cent, 4.5 per cent and 4 per cent -- was 40 per cent higher than the increases CN negotiated in recent collective agreements for a comparable three-year period," he said.

"And the UTU's final offer on lump sum bonus payments, $1,000 per year over the three-year period, was three times greater than the recent agreements."

Hallman noted the average 2006 annual wage increase in major collective agreement settlements in the private sector in Canada was 2.1 per cent, and it was the same figure in the transportation sector.

He said the average 2006 annual income for UTU employees was $75,000, with one-quarter of those making more than $90,000.

There are no plans to resume contract talks between CN management and the union.

CN says commuter lines in Toronto and Montreal, and Via passenger train schedules, will not be derailed.

"We don't want to inconvenience the citizens of Toronto or GO Transit," Glen Dower, local chairman of the UTU, said on Sunday. "Our fight is with CN Rail."

GO Transit says it will keep customers regularly posted of developments through its website and e-mail alerts.