Novak Djokovic's visa has been cancelled and his Australian Open campaign is in tatters. 

The tennis star was told to leave the country today but reports suggest he will challenge the decision in Victoria's courts. 

Djokovic will reportedly be transported to a quarantine hotel in the city before boarding a flight back to Europe and is expected to challenge the decision in Victoria's courts. 

Prime Minister Scott Morrison tweeted on Thursday morning: "Mr Djokovic's visa has been cancelled. Rules are rules, especially when it comes to our borders. No one is above these rules. 

"Our strong border policies have been critical to Australia having one of the lowest death rates in the world from Covid, we are continuing to be vigilant." 

But speaking in a press conference on Thursday morning, Mr Morrison revealed there had never been an exemption in place and Djokovic's evidence for a medical exemption was "insufficient". 

"I want to thank the Border Force officers for doing their job implementing the Government's policies, they haven't done it their job, entry with a visa requires double vaccination or a medical exemption," he said. "I am advised that such an exemption was not in place, and as a result, he is subject to the same rule as anyone else. 

"I also want to stress, that ultimately, this is the responsibility of the traveller. It is for the traveller to be able to assert and back up their ability to come into the country consistent with our laws. 

"I will take advice from many places, no advice was provided by the Commonwealth government. They can take advice, but it is up to them at the end of the day, and if they do not comply with the rules, that the Australian Border Force will do their job and they have done their job. This is nothing about any one individual, it is simply a matter of following the rules, and so those processes will take their course, over the next few hours, and that event will play out as it should." 

Mr Morrison added that it is not uncommon and that entrants to Australia need to be double vaccinated, which is assessed at the border. 

He also said it is on the traveller to have the proof to show why they have not been vaccinated. 

"He provided information to the airline to allow his entry onto the plane but people get on the plane, that is not an assurance that they will be able to come through Australia's border at the other side," Mr Morrison said. 

"The problem is not necessarily with the visa. There are many visas granted and if you have a visa and are double vaccinated you are very welcome to come. And I think what this says to everybody in Australia the people are welcome but if you are not double vaccinated and not an Australian resident or citizen, you cannot come." 

Mr Morrison added that Djokovic had not been singled out and he did not believe this situation would impact Australia on the global stage. 

This is despite Serbian President Aleksander Vucic vowing his nation "will fight" the "maltreatment" of the tennis star. 

"Serbia has been a good friend of Australia and provided very strong support particularly on security issues globally and we greatly appreciate that," he said. "This is a very specific case that deals with one individual and Australia's sovereign border laws and their fair application." 

Mr Morrison said Djokovic was not singled out but that any extra scrutiny was due to Djokovic's own doing. 

"When you get people making public statements of what they say they have and what they are going to do and what their claims are, they draw significant attention to themselves," he said. "Whether they are a celebrity, a politician, a tennis player, a journalist, whoever does that, they can expect to be asked questions more than others before you." 

In a potentially massive twist, Reuters and The Herald Sun are reporting three other players with similar exemptions to Djokovic's have already entered the country without incident. 

The Herald Sun added Djokovic's lawyers were already preparing to challenge the ruling in court.