The United States visa waiver program has recently implemented changes where Australians who have recently visited some countries in the Middle East will no longer be able to enter the country under the program.

Those who have travelled to Iran, Iraq, Sudan or Syria on or after March 1, 2011 won't be able to enter the country under the program due to changes introduced overnight under the Visa Waiver Program Improvement and Terrorist Travel Prevention Act 2015.

The new rule is also applicable to nationals of those countries except to limited exceptions such as those who travelled for military or diplomatic purposes. It means those travelling to the U.S. who also hold a passport from any of the four countries named will have to apply for a visa through the regular process at an embassy or consulate. Those who already have valid Electronic System for Travel Authorizations (ESTA) will have them revoked.

The change is one of the United States' response to concerns over terrorism and the rise of the Islamic State. These new rules were included in a bill passed by the U.S. congress last month. It will affect citizens of 38 countries, mostly in Europe, who are eligible to use the visa waiver system and a new, more detailed, ESTA questionnaire will be released in February 2016.

A spokesman for the Department of Foreign Affairs and Trade said the government has updated the Smartraveller website to advise of the changes.

'Further updates will be made to Smartraveller over coming weeks in line with any additional advice provided by the United States government. We recommend that all travellers subscribe to this advice to stay informed,' he said.

The U.S. Department of Homeland Security said certain travellers may be eligible for a waiver under the new rules including journalists, aid workers or those travelling for business purposes.