The political stoush over immigration policy has spilt over into the Prime Minister's own office, with the Coalition targeting Julia Gillard's communications director who holds a 457 visa.
The opposition accuses Julia Gillard of demonising foreign workers; the government alleges Tony Abbott is discriminating against Australian workers.
The government and opposition have been trading barbs over 457 visas, with Opposition Leader Tony Abbott accusing Ms Gillard of ''demonising foreigners'' for her comments that ''Aussie workers'' should be put at the front of the jobs queue.
Ms Gillard has countered that the opposition was taking a cynical approach to the immigration issue and that Mr Abbott's words ''ring hollow''.
On Tuesday, shadow treasurer Joe Hockey took a swipe at the Prime Minister over staff in her office, referring to Ms Gillard's communications director, John McTernan, who is a British citizen.
"Julia Gillard says people on 457 visas are taking the jobs of everyday Australians, aren't there people in her office who are on 457 visas?" Mr Hockey asked.
"And how did they get security clearance to access some of the most sensitive documents of Australia?
"I'm just surprised that there's no one else that is prepared to work in Julia Gillard's office than someone who's on a 457 visa. I seem to recall that under the previous government people on 457 visas were not allowed to work in ministerial offices. But I could be wrong.''
A spokeswoman for Ms Gillard said that the office did not comment on individual members of staff but the ABC reports that Mr McTernan has confirmed he holds a 457 visa.
The spokeswoman said that Mr Hockey's comments were an example of more ''relentless negativity from the Opposition''.
''Joe Hockey's personal attack on staff members is a blatant attempt to divert from his own press conference where he bluntly contradicted Tony Abbott on whether the opposition would scrap household assistance payments and was exposed on the Coalition's cuts,'' she said.
She said ''all members of staff must meet relevant security clearance requirements''.
'False birth place war'
Ms Gillard reignited the 457 debate in a speech in western Sydney on Sunday night, marking the start of her mini-campaign in the area. The Prime Minister said she had a five-point plan to improve the future and make life easier for people in western Sydney.
Along with the national broadband network and national disability insurance scheme, this included the promise:
''We will support your job and put Aussie workers first.''
As she concluded her speech she told the audience she had a plan to ''stop foreign workers being put at the front of the queue with Australian workers at the back''.
On Monday evening, Mr Abbott said that he found Ms Gillard's comments ''jarring''.
''I tell you what we'll never do,'' he told SBS television.
''We won't run around the place demonising foreigners the way the Prime Minister has sought to do over the last 24 hours.''
People on 457 visas, who have come to Australia ''the right way'', were the best possible migrants, the Opposition Leader said.
''The point of being prime minister is that you've got to be a national leader, not just a tribal chief,'' he said.
Talking to reporters in Melbourne on Tuesday, Mr Abbott added that 457 visa workers made a "great contribution" to Australia from "day one".
"The government is tolerating people coming to this country and going on welfare and they're demonising people coming to this country and working from day one," he said.
He said Ms Gillard was trying to divide Australians "yet again".
"First of all we had the false class war, then we had the false gender war, now we've got the false birth place war."
Ms Gillard hit back, saying the opposition was taking a cynical approach.
''You know as well as I do that those words ring hollow in the mouth of the Leader of the Opposition,'' she told Sky News.
Speaking from Sydney, Ms Gillard said that the Coalition had been trying to raise fear in the community on asylum seeker issues since before the 2010 election.
She again expressed concern that Mr Abbott planned to make temporary foreign labour a ''mainstay'' of the Coalition's immigration policy.
Ms Gillard said that the government responded to evidence when making policy, adding that the migration system should be about permanent migrants coming to Australia, ''getting a job, being real contributors''.
Labor and unions are worried that 457 visas are being abused by employers and Australian workers are missing out on jobs.
The ACTU estimates that in the construction sector alone there has been a 38 per cent rise in 457 visas issued, while jobs in the sector are declining.
The Prime Minister said Australians needed to be reassured that the 457 visa program was being properly administered so Australian workers knew ''if they're there with the skills, ready to do the job, then they get the job''.
Her comments follow an announcement from the government last week that it would crack down on 457 visas for temporary foreign workers.
Call for calm
The Migration Institute's chief executive, Maurene Horder has called for the calm on the 457 debate, telling ABC Radio that politicians should focus on the facts.
''I just think we need a steady mind and calm conversation going on around it, and not pitting Australian workers against some of these overseas people,'' she said
''That's the thing I'm a little bit alarmed about - that we don't develop a political bunfight for the purposes of an election.''
Last week, the Australian Mines and Metals Association chief executive Steve Knott said there was no evidence his industry misused the 457 visa scheme, or was even a heavy user of migrant workers.
No dog whistle
On Monday – before Mr Abbott's comments – Home Affairs Minister Jason Clare dismissed the suggestion that Ms Gillard was dog whistling on the subject.
Mr Clare, who holds the western Sydney seat of Blaxland, said Ms Gillard's focus on Australian jobs was great for Australia, noting that his electorate had an unemployment rate almost double the national average.
''I think there's a very very big difference between the Prime Minister saying she supports creating jobs in Australia and some of the things you've heard from the opposition in the last few days,'' he told ABC Radio, in reference to Coalition immigration spokesman Scott Morrison's call last week for police to be notified about asylum seekers in their area.
With AAP, Bianca Hall