Four of Austrlia's biggest cities are now among the most expensive places in the world to live in according to a new global survey published this Thursday.

The Economist Intelligence Unit's biennial cost of survey revealed that Sydney and Melbourne now rank sixth and seventh in the world's most expensive cities to live in. Perth and Brisbane also made the top twenty with ranks of 13th and 14th respectively.

This sharp rise comes after the Australian dollar has moved to an equal rate of exchange with the US dollar. Ten years ago Sydney was ranked 71st and Melbourne 80th, Perth and Brisbane were ranked 91st and 93rd respectively. This year it is now cheaper to live in London, Vienna, Rome, Berlin, Hong Kong and Beijing than most Australian cities.

"Australia has long been an attractive destination ... Whether the spiralling relative cost of living will dampen this appeal remains to be seen," said Mr. John Copestake, the Economist survey author.

Tokyo was once again the most expensive city a rank which it has held over the last two decades. Another Japanese city, Osaka was ranked third.

"Low inflation and poor consumer confidence have persisted in Japan, but the yen has strengthened significantly over the last two years, pushing Tokyo back to the top of the ranking last year," the survey said.

"This year the cost of living has increased further in Tokyo, despite the human and economic cost of the earthquake and tsunami that hit Tokyo in March, and the subsequent nuclear reactor scare in Fukushima."

The top ten most expensive cities are:

  1. Tokyo, Japan
  2. Oslo, Norway
  3. Osaka Kobe, Japan
  4. Paris, France
  5. Zurich, Switzerland
  6. Sydney, Australia
  7. Melbourne, Australia
  8. Frankfurt, Germany
  9. Geneva, Switzerland
  10. Singapore, Singapore

The 10 cheapest cities to live in were mostly found in South Asia with the Pakistani port of Karachi being the least expensive city in the world to live in. Other cities in the bottom 10 were Mumbai, Tunis, Tehran, New Delhi, Jeddah, Algiers, Panama City, Manila, and Dhaka in Bangladesh.