ACT Deputy Chief Minister Katy Gallagher said yesterday the economy was under enormous pressure.

''I think the time at the moment is to keep people in jobs rather than, I guess, making extravagant wage claims, which could put pressure on jobs ultimately,'' she said.

''At the same time, I understand, you know, people need to live. Cost of living is increasing so what we'll be doing at doing here is the ACT is making reasonable wage offers but mindful of the fact that our budget is under pressure and we won't be able to meet the claims that unions come forward with.''

Acting Prime Minister Julia Gillard urged unions yesterday to exercise restraint when making wage claims in tough economic times.

''In this country the Government has been acting to keep our economy moving and our main aim is to protect jobs and to invest in jobs,'' she said. ''My call today to unions and to employers is to put jobs first.

''We want to make sure that Australians have the benefit of work, I would expect that to be at the forefront of people's minds as they negotiate workplace arrangements for their enterprise.''

Earlier, the Construction, Forestry, Mining and Energy Union demanded a 33 per cent pay rise for some workers at Alcoa's aluminium plant in Western Australia.

The company has unveiled plans to slash more than 13,000 jobs worldwide.

ACTU president Sharan Burrow defended the wage claim. ''We have to look at the circumstances. Alcoa will tell you whether these workers, and they're one group of workers, are in fact skilled workers they can't maintain unless they pay reasonable pay increases,'' she said. ''And of course you have to look at the fact that this is, you know, potentially a three-year agreement.''

Ms Burrow warned the economy would suffer if workers could not afford to pay their bills.

''Well what Julia Gillard urged workers ... [was to] do everything possible to protect jobs and she urged people entering into bargaining to be very creative about the protection of jobs,'' she said.

''But what we know as well is that if you don't protect incomes, then that's a negative for the economy as well.

''If working people can't pay their bills, if in fact their mortgage is threatened then that's not going to help the economy survive, nor indeed recover.''

Opposition employment participation spokesman Andrew Southcott said union demands for ''excessive wage increases'' would put jobs in jeopardy.

''The Rudd Government cannot afford to pander to the unreasonable demands of unions that may threaten the job security of the very people they claim to represent,'' he said.

''The CFMEU demands for up to a 33 per cent wage increase for Alcoa workers is a prime example of irrational union demands.

''Times are tough for many Australian businesses. The Rudd Government needs to ensure that their policies do not make it tougher for businesses to retain their staff.''