MONTREAL, Aug 25 (Reuters) - A decision obliging more

than 9,000 Canadian rail workers to stay on the job is a win for

the railways and could impact bargaining in other federally

regulated sectors like aviation, the head of a Canadian rail

workers' union told Reuters.

Paul Boucher, president of the Teamsters Canada Rail

Conference, also said the union would work with other labour

groups as it mounts a legal challenge to a Saturday decision

that halted work stoppages at the country's two largest railways

and imposed arbitration.

While the Teamsters will obey the order to return to

work, the union has warned it could lead to the imposition of

future contracts, eroding workers' bargaining power. The

decision comes as Air Canada ( ACDVF ) pilots press for a new

contract and can commence job action as early as mid-September

if there is no agreement with the country's largest carrier.

Air Canada ( ACDVF ) said on Sunday its intent is to reach a

negotiated settlement with the pilots over the coming weeks.

"Any federally regulated company, it's a win for them at

this point," Boucher told Reuters in his first interview since

the Thursday lockout. "This is disastrous for labour, for

workers."

The Canada Industrial Relations Board made the decision

after Labour Minister Steven MacKinnon asked it on Thursday to

end an impasse in separate talks between the Teamsters, Canadian

National Railway ( CNI ), and Canadian Pacific Kansas City ( CP )

.

The dispute, which triggered a first ever lockout of

Teamsters workers on Thursday at both freight rail carriers, led

to unprecedented disruptions that threatened to hammer Canada's

export-driven economy, leading agricultural businesses to plead

for relief.

CN has said the company would have preferred a negotiated

agreement, but was satisfied that the labour stoppage is over.

Spokesperson Jonathan Abecassis said on Sunday that CN tried to

get an agreement for nine months and made five offers that would

have improved wages and working conditions but the union did not

engage.

Both railways have said they are focused on restoring

service, with the Teamsters calling off a CN strike on Monday,

but planning to appeal the decision in federal court.

"This historical moment is so extremely important that

labour needs to get involved and they will," Boucher said.

"We're going to be calling on all labour across Canada to

join our fight and take this all the way."

Other unions could participate as intervenors in their legal

case and lend moral support to the Teamsters, Boucher said.

The 58-year-old Boucher, who once struggled to keep his

on-call rail job while raising a child as a single dad, has been

bargaining with CN out of a second-floor conference room at a

downtown Montreal hotel.

The Teamsters union disagreed with CN and CP over

scheduling, shift duration and availability. CN, for example,

wants employees to work up to 12-hour shifts, compared with 10

hours in the current agreement, a move opposed by the union.

Boucher said he has been in contact with the union

representing more than 5,400 Air Canada ( ACDVF ) pilots who approved a

strike mandate last week.

The Air Line Pilots Association (ALPA) which represents Air

Canada ( ACDVF ) pilots, and CPKC were not immediately available for

comment.

A spokesperson for Canada's labour minister was not

immediately available for comment on whether the decision to

impose binding arbitration on railways would serve as a

precedent in other sectors, including aviation.