UPDATE 1-Oil producer Norway starts wage talks to avert widespread strikes

* Private sector firms begin talks with labour unions

* All major industries involved, including oil, gas

* Risk of strike unless agreement by April 7 deadline(Adds pix, employers' comment in 5th paragraph)

By Camilla Knudsen

OSLO, March 12 (Reuters) - Norwegian employers and labourunions embarked on four weeks' of wage talks on Monday to staveoff widespread strikes that risk impacting output in westernEurope's biggest crude producer.

Unlike most years, in which wages are set on anindustry-by-industry basis to reduce complexity, the 2018 roundrolls a majority of private sector firms into a singlenegotiation in a bid to resolve a stand-off over pension reform.

"We've understood that there is no real will among employersto compromise from the outset," labour union negotiator AsleReime, who will represent oil workers, told Reuters ahead of thetalks.

"Pension rights are important to all workers regardless ofwhich industry they are in, that's why I think there is moreweight behind the demands this year and also more willingness tostrike," he added.

While employers are willing to discuss an increase ininflation-adjusted pay, it will be more difficult to meetdemands for better pensions and change in travel-relatedcompensation, Confederation of Norwegian Enterprise (NHO) ChiefExecutive Kristin Skogen Lund told reporters.

If initial talks break down, a state-appointed mediator willattempt to broker a deal in the final days leading up to anApril 7 deadline, after which most workers are allowed to go onstrike unless an agreement is found.

A few days in advance, Labour unions must name the companiesthat would be hit in a first wave of industrial action, makingit difficult to predict how extensive an initial walk-out couldbe.

While Norway's production of oil and natural gas is unlikelyto be targeted from the start since the contract for rigworkers' is valid until June, unions may still hit the sector byshutting down yards and other suppliers.

Onshore processing and export facilities for natural gas arealso at risk of strike, unions said, while offshore oilproduction workers could become involved in any extended strike.

Western Europe's largest producer of oil and gas pumps abouttwo million barrels of crude, condensate and natural gas liquids(NGL) per day, while its output of natural gas stands at around320 million cubic metres per day.

Norway's last major strike by oil workers took place in 2012and lasted for 16 days before the government intervened to forcean end to the conflict, citing vital national interests.

Top companies that could be affected by the talks includeconsumer goods maker Orkla, fertiliser maker Yara, metals producer Hydro and oil servicescompanies Aker Solutions and Kvaerner.

Also at risk are major oil firms including Statoil,Aker BP, Lundin Petroleum and Shell.(Editing by Terje Solsvik, editing by Louise Heavens and DavidEvans)