Matt Chambers, The Australian
Mr Clifford says that Qantas is already straining under the cost of $US100-a-barrel oil prices.
He also said the unions were lacking leadership and attributed a recent increase in industrial disputes across the business sector and a drop off in focus on productivity partly to the federal government's Fair Work laws.
"With the sort of things they are trying to do get up, I guarantee there will be fewer jobs," Mr Clifford told The Australian as Qantas remained locked in an industrial relations brawl that threatened to lead to strikes after the Easter weekend.
"Union leaders have been emboldened by the recent legislation.
"There is very little focus on productivity and we seem to have lost the enterprise focus of the last 15 years or so."
It is the first time Mr Clifford, who as head of Rio Tinto successfully stared down unions at the company's iron ore and coal mines, has weighed in on the latest Qantas trouble.
Qantas engineers and pilots have already threatened to strike if claims, including job security guarantees, are not met, while the Transport Workers Association, which represents 9000 other Qantas workers, is also threatening action.
The TWU wants the airline to agree to job security clauses under which any contract struck by the airline would equal the pay and conditions of the union agreement. It says this will remove the incentive to contract out work.
Mr Clifford asked "what planet" union leadership was on, and pointed at surging oil prices and increased competition as obvious indicators the airline was working in a tough environment.
"I hope we will see some common sense prevail," Mr Clifford said, adding that there was probably a lack of leadership and evidence of inexperience in the top ranks of the unions.
He said the calls for job security made no sense since the measures being asked for would result in lost jobs because of the effects they would have on the airline.
Mr Clifford also dismissed industry rumours that he was unhappy with the tack chief executive Alan Joyce had been taking on the issue.
"Alan Joyce and I are on the same page, we are in lock step," Mr Clifford said.
Mr Joyce has accused the unions of running a "kamikaze" campaign that was likely to drive customers to competing airlines.
Investment bank CLSA says the number of workplaces conducting votes on strikes has surged in the past year.
Its research shows there are 16 listed companies with industrial relations issues that have been simmering this quarter.
Under the legislation, employees have voted for the right to strike at Adelaide Brighton, BHP Billiton's Mt Arthur Coal operation, Boom Logistics, Coca-Cola Amatil, Downer EDI's rail unit, GWA Bathrooms and Kitchens, Transfield and UGL.
Workers at Monadelphous, QR National and Salmat have been given the right to vote on strike action, while Lend Lease, Mirvac, UGL and Wesfarmers' Coles unit are attempting to stop industrial action taking place through court orders, CLSA says.
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