CANBERRA, April 17 (Xinhua) -- The Migration Council of Australia (MCA) has called for the winner of the nation's upcoming general election to overhaul its immigration system.

Carla Wilshire, chief executive officer of the MCA, warned that since the Department of Immigration was incorporated into the Department of Home Affairs in December 2017, it has been under-resourced.

"I am increasingly concerned that the migration program is not being properly managed," Wilshire told News Corp Australia on Wednesday.

"Fixing this will be a big job and it needs to a priority of an incoming government of any persuasion.

"Australia's citizenship backlog is now the largest in our history with well over 220,000 people waiting to have their applications progressed.

"We have an unprecedented build-up of spouse visas with the queue growing to tens of thousands and we have up to 30,000 people claiming asylum each year arriving by plane."

If elected for a third term in the general election on May 18, the incumbent Liberal-National party coalition (LNP) has promised to reduce the cap on Australia's annual permanent migration intake to 160,000, a plan that Wilshire said could harm Australia's economy.

Under its proposed immigration plan, the LNP will also direct a larger number of migrants to Australia to regional areas in an attempt to ease the strains that population growth is putting on major cities such as Sydney and Melbourne.

However, that plan was on Wednesday described by the Grattan Institute, the country's leading policy think tank, as a "dangerous fantasy", according to The Australian.

"Despite policy experience, wishful thinking persists that government policy can somehow shift significant populations from capital cities to regions...But it is a dangerous fantasy. It provides an excuse for governments to avoid making the hard decisions that would improve housing affordability and how our cities work," the institute said in its "orange book" of priorities for the next government.

"Even if the scheme were successful in increasing migration to regions, it would not reduce city population pressures. Net overseas migration is dominated by...international students and working holiday ('backpacker') visas," it added.