Visa approval will be sped up, to just five days, for temporary overseas workers if an employer is unable to find skilled local workers to do the job, Julia Gillard said.

Unions are unhappy with the speeding up of the ''457'' visa program, warning it could be used to drive down local wages and was ripe for exploitation.

But business groups welcomed it as critical to preventing a skills shortage and wage pressure as Queensland rebuilds roads and rail, and competes with the mining industry for labour.

Construction unions have lobbied hard against the employer-sponsored visa category in the past, which they say has been abused in the building industry to bring in large numbers of low-paid Chinese workers in sham contracting scams.

The ACTU president, Ged Kearney, said 457 visas should only be granted for Queensland projects where there was a genuine need. ''No one wants to see a return to the sorts of abuses we saw under the former Coalition government where unscrupulous employers were allowed to exploit overseas workers,'' Ms Kearney said.

The Australian Manufacturing Workers Union national secretary, David Oliver, said: ''We want to make sure we have the right checks and balances, and proper market rates are being paid.''

But the Australian Industry Group chief executive, Heather Ridout, said speeding up visa approvals ''is the right call''. The move was also welcomed by the Business Council of Australia.

The Labor government had moved to tighten the list of applicable 457 occupations in the wake of the financial crisis.

Ms Gillard said the flood recovery measures would also boost the ability of local jobseekers to fill vacancies on Queensland rebuilding projects. Expanding a relocation program for the unemployed from 2000 to 4000 places would ''get them to where the jobs are''.

Single job-seekers who have been out of work for three months will be paid up to $6000 in incentives, and families $9000, to move to a regional Queensland area to take a job. Flood areas would be added to the relocation priority list, and job-seekers willing to move for six months enlisted.