A coalition government will cut down Australia's immigration intake back to a reasonable level, according to shadow treasurer Joe Hockey.

Opposition Leader Tony Abbott is expected to announce the immigration numbers will be held to no more than 170,000 a year if he wins at the August 21 election. At its peak two years ago, admissions reached 300,000.

"The Australian people are concerned by the lack of integrity in immigration programs at the moment," Mr Hockey said.

"We are responding accordingly, our numbers take us back to a reasonable level."

Dismissing the measure, the Gillard government claimed current projections show that the target intake will just about be reached anyway by June next year.

Ms Gillard said in a recent debate that Mr Abbott was being convenient with the truth.

According to the prime minister, the Labor government had already slashed the immigration numbers from 300,000 in 2008 to 175,000 this year, with further cuts in the pipeline.

"So the trick here, and I think Tony should really reveal the trick, the trick here is Tony today has promised the Australian people what I'm already delivering to the Australian people," Ms Gillard said.

Meanwhile, business and industry groups criticise the policy does nothing to solve the growing shortage of skilled workers that is likely to cripple productivity.

Recent reports have showed the nation's most prominent business figures calling for intake of skilled outlanders, saying Australia's economy will deteriorate and inflation rise if the admission of skilled migrants is not maintained at least at its current level.