The Australian government has upgraded the threat level for Qatar and Oman, warning the security situation in the Middle East continues to be volatile.
As protests in Iran continue, the airspace over the country was abruptly closed today, leading to concerns that unrest in Iran could spread.
Smartraveller has officially advised Australians to exercise a high degree of caution when in the country, and has made the same designation for Oman.
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"The security situation in the Middle East is unpredictable," it said.
"Media reports indicate some personnel were advised to leave the Al Udeid Airbase on 14 January," referring to the airbase in Qatar which houses US and UK forces.
The US is evacuating hundreds of its forces from bases in the region.
The Australian government continues to urge citizens not to travel to Iran, and if they still remain in the country, to leave as soon as possible.
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Over 2500 people have died in protests that have swept across the country, with some experts believing Iran's regime could be on the brink of collapse.
"Be prepared to shelter in place for an extended period. Make sure you have supplies of water, food and medication," Smartraveller warns.
There are six nations in the Middle East where the Australian government advises Aussies against all form of travel, including Iraq and Yemen.
Israel, which is involved in a conflict in Gaza, is currently at the second-highest threat rating, which is "reconsider your need to travel".
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