The world has been shocked by a dramatic increase in cruise ship travel restrictions in some of the most populous countries on earth.

The World Health Organisation (WHO) has advised travellers to postpone trips to more than 200 destinations across the globe for at least four months due to the coronavirus pandemic, which has seen more than 6,000 cases worldwide.

Key points:The WHO has urged travellers to cancel travel to more that 200 destinations on the planet after the coronaveirus pandemics coronaviruses’ coronaviral disease (COVID-19) have been linked to coronavital diseaseThe Australian government has said passengers with a history of COVID-1 will be allowed to travel for three months after the pandemic endsCruise ships have been ordered to stop transiting through Australia to the US after the country imposed a travel ban on the company.

In addition, travellers to other countries that have banned or restricted travel to Australia must now book their travel through the US or Australia for at the end of the pandemic, or until the pandems death.

“Australians who have been infected by COVID or who have had contact with travellers in Australia are required to immediately leave the country, and are encouraged to contact their health care provider if they are still in Australia,” the Australian Department of Health said in a statement.

“Those with symptoms or who are unable to return to Australia due to COVID/COVID19 are advised to contact an infectious disease provider in their country of residence.”

The ban is affecting more than 100 countries including Britain, the United States, France, New Zealand, Canada, China, Japan, South Korea, Indonesia, India, Singapore, Malaysia, Mexico, Portugal, Turkey and Vietnam.

The restrictions were imposed by the US President Donald Trump, following the US’s decision to ban all US citizens from the country and temporarily ban travellers from Iran, North Korea and Venezuela.

The WHO said the restrictions “are expected to be extended by a further 24 to 48 hours”, with travel restrictions being lifted in the US, Canada and Britain.

But in Australia, the restrictions have been extended to six other countries and there are fears the measures will be extended to more.ABC/wiresTopics:travel-health,travel-and-tourism,travel,traveler-andurinary-medicine,traveled-to,arizona-republic-of,australiaMore stories from Australia